A K+S mine rescue team covers an area the size of Munich ... · A K+S mine rescue team covers an area the size of Munich Micrometers Precision in manufacturing ventilators Hot Pellets

Underground Mining A K+S mine rescue team covers

an area the size of Munich

Micrometers Precision in manufacturing

ventilators

Hot Pellets How they trigger gas alarms

Reliable measurement provides protection

New Drugs Are Invisible

The Magazine for Safety Technology February 2010

Dräger Review 99

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Dräger review 99 | February 2010

ExpEriEncE 4 people who perform

She has worked in New york City emergency rooms for 27 years; he has worked in the mines of australia for 28 years.

nEws 6 news from the world of Dräger THC

test even more sensitive. Subsidiary in Finland. reaccreditation of the TestCenter, and buying back Siemens’ 25 percent holding in Dräger Medical ag & Co. Kg.

Focus 8 new Drugs — new strategies

The use of known drugs such as alcohol and canna bis is growing strongly. but drugs such as ritalin also impair safety. Precise measurements and systems also protect against these new dangers.

roughly 66,000 m3 of fresh air are pumped into the shaft system of K+s KALi GmbH’s werra mine

each minute. This enables the use of diesel vehicles underground. read more starting on page 16.

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Detecting danger for over half a million users worldwide.

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FOR MORE INFORMATION VISIT: WWW.DRAEGER.COM

100% developed and manufactured by us, our innovative instruments use unequalled technology and leading edge, long-life sensors – up to 5 years! Built to outlast our competitors’ and detect the widest range of gases and vapors, our sensors offer better selectivity and a low cost of ownership. Resilient in use, they also save you money and ensure accuracy and reliability, even in extremely demanding conditions.

Safety begins with a DrägerSensor®.

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3Dräger review 99 | February 2010

Contents

experienCe 4 people who perform

She has worked in New york City emergency rooms for 27 years; he has worked in the mines of australia for 28 years.

news 6 news from the world of Dräger THC

test even more sensitive. Subsidiary in Finland. reaccreditation of the TestCenter, and buying back Siemens’ 25 percent holding in Dräger Medical ag & Co. Kg.

FoCus 8 new Drugs — new strategies

The use of known drugs such as alcohol and canna bis is growing strongly. but drugs such as ritalin also impair safety. Precise measurements and systems also protect against these new dangers.

report 14 Dangerous Cocktail Measurement of

the pilot substances provides an initial overview of what might be contained in fire gases of unknown composition.

16 protection for the underground City The mine rescue team at the K+S KaLi gmbH werra mine discovers an area the size of Munich and its surroundings. a visit 1,000 meters underground.

BaCkgrounD 20 Hot pellets trigger gas alarm

How does the detection of flammable liquids work? Part 2 of the series explains the details.

insigHt 24 precision down to the Last

Micrometer is required to manufacture long-lasting and reliable ventilators.

outLook 28 research for the Future of

Fire fighting The objective is to find answers to the challenges of the future.

serviCe 31 where and who? Dräger worldwide,

Publishing information

CLose-up 32 gas Detection Device The X-zone

5000 Portable gas Detector cannot be overlooked or overheard.

roughly 66,000 m3 of fresh air are pumped into the shaft system of k+s kaLi gmbH’s werra mine

each minute. this enables the use of diesel vehicles underground. read more starting on page 16.

16 Mine 28 researCH8 BLow

Detecting danger for over half a million users worldwide.

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FOR MORE INFORMATION VISIT: WWW.DRAEGER.COM

100% developed and manufactured by us, our innovative instruments use unequalled technology and leading edge, long-life sensors – up to 5 years! Built to outlast our competitors’ and detect the widest range of gases and vapors, our sensors offer better selectivity and a low cost of ownership. Resilient in use, they also save you money and ensure accuracy and reliability, even in extremely demanding conditions.

Safety begins with a DrägerSensor®.

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4 Drägerheft 384 | februar 2010Dräger review 99 | february 2010

ExpEriEncE PeoPle who Perform

peter Hatswell, mine safety and rescue specialist, Blue Mountains / Australia

“When you’re underground, the most important rule is ‘Pay atten-tion.’ You have to develop an intuitive awareness of possible dan-gers. Monitor your environment, the atmosphere, ground condi-tions, and the like. Take a noise that I’ve known for years — does it sound just a bit different today? There are outstanding safety devices in our mines, early warning systems that are almost per-fect, but the most important element is people’s attitude. I’ve been working in mines for 28 years now.

I’ve trained hundreds of miners in mine rescue techniques all over Australia. In many cases I know the people who are waiting to get help or even to be rescued. That’s what happened in Beacons-field, Tasmania, in 2006. A part of the gold mine there collapsed, trapping two miners 1,000 meters under the surface. I knew one of them personally — and not just him, I knew his whole family. We

Susan Schwartz, chief certified registered nurse Anesthetist, new York city / U.S.“after 27 years working as a nurse in New york City there is not too much that can challenge me. So when i was asked to join a pediatric medical mission to latin america i jumped at the offer.

when we entered the medical compound in honduras i was stunned at the number of children who had arrived for the screening. the facial deformities on these children, which included cleft lips and palates, were more severe than i was prepared for. i was humbled when they gave us a standing ovation just as we stepped off the bus.

these children came from all over honduras, brought by their parents and siblings, often on foot, or by hitching a ride. many camped outside of the makeshift hospital, sleeping in the dirt and eating out of the gar-bage just to be there in the morning in the hope that their child would

get onto the operating room schedule that week. i was so moved that i vowed to make it a yearly mission and to do more charitable work.

i graduated from Columbia university School of Nursing anesthesia. i practically grew up with Dräger. they have been with me every step of my career. So you can imagine my sheer joy when i saw a Narkomed 1a in the or in San Pedro Sula honduras on that first day. it was like meet-ing a dear old friend in a foreign country. Dräger was watching over my shoulder and that was very comforting to me in a strange place.

i really don’t like to talk much about what i did, as it is small in com-parison to what those less fortunate must endure on a daily basis. i am writing this only to inspire others to share their gifts. you will get more in return than you give and your life will be more meaningful.”

What Moves Us — Dräger Worldwide

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5Drägerheft 384 | februar 2010

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Dräger review 99 | february 2010

Peter Hatswell, mine safety and rescue specialist, blue Mountains / Australia

“When you’re underground, the most important rule is ‘Pay attention.’ You have to develop an intuitive awareness of possible dangers. Monitor your environment, the atmosphere, ground conditions, and the like. Take a noise that I’ve known for years — does it sound just a bit different today? There are outstanding safety devices in our mines, early warning systems that are almost perfect, but the most important element is people’s attitude. I’ve been working in mines for 28 years now.

I’ve trained hundreds of miners in mine rescue techniques all over Australia. In many cases I know the people who are waiting to get help or even to be rescued. That’s what happened in Beaconsfield, Tasmania, in 2006. A part of the gold mine there collapsed, trapping two miners 1,000 meters under the surface. I knew one of them personally — and not just him, I knew his whole family. We

managed to get both of them out after two weeks, and before that we were able to talk with them. ‘I won’t be happy until I’ve sent you two to a hospital,’ I called out to them. It might sound strange to want someone to be in the hospital, but that’s how it was. I’ll never forget the relief we felt the day we got them out. Our decades of experience had paid off. My father was the fire chief in our small town near Sydney. Today I’m the captain and I’m in charge of safety, at home and down in the mine out in the desert. We have to detect gases — but the main thing, which is even more important underground than aboveground, is that we have to be able to breathe and have faith in the apparatus we use. That’s why I complete a training program in apparatus maintenance every year. The thing I appreciate most of all about Dräger technology is its reliability. But I guess just about everybody will tell you that.”

Susan Schwartz, Chief Certified Registered Nurse Anesthetist, New York City / u.S.get onto the operating room schedule that week. i was so moved that i vowed to make it a yearly mission and to do more charitable work.

i graduated from Columbia university School of Nursing anesthesia. i practically grew up with Dräger. they have been with me every step of my career. So you can imagine my sheer joy when i saw a Narkomed 1a in the Or in San Pedro Sula honduras on that first day. it was like meet-ing a dear old friend in a foreign country. Dräger was watching over my shoulder and that was very comforting to me in a strange place.

i really don’t like to talk much about what i did, as it is small in com-parison to what those less fortunate must endure on a daily basis. i am writing this only to inspire others to share their gifts. you will get more in return than you give and your life will be more meaningful.”

What Moves us — Dräger Worldwide

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6 Dräger review 99 | February 2010

News


New subsidiary in FinlandOctober 2009 saw the launch of a new Dräger subsidiary in Helsinki, Finland. For more than half a century before, the trading company Liitin Oy had represented Dräger’s business interests in the country with both great commitment and success. Now all business activities are being managed by the new subsidiary, Dräger Suomi Oy, which has taken over the entire workforce, customer base, and inventory. “we already have our own subsidiaries in the other Scandi- navian countries, and this move will further strengthen our business activities in the region,” says Marko wittich, vice President at Dräger (safety division).

The Finnish workforce, which will now have direct access to the training programs offered within the group, is looking to increase the company’s already substantial market share among fire departments as well as to tap new market potential. “First and fore-most, we’re banking on further growth in the areas of service and aftersales,” explains wittich, who sees the com pany’s nationwide service as a major plus factor in this sparsely populated country. The business interests of Dräger’s medical division in Finland are currently being represented by the group’s Swedish subsidiary together with a Finnish specialist dealer.

Marko wittich and Johan Kinnula, Dräger suomi Oy.

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Dräger Repurchases siemens stakeat the end of 2009, Dräger announced that it was to buy back the 25 percent stake in Dräger Medical ag & Co. Kg held by Siemens ag, Munich. “Purchasing this stake at an acceptable price will boost group earnings in 2010. This move also reduces complexity and allows us to establish ourselves as an integrated tech - nology group,” said Stefan Dräger, Chairman of the executive board of Dräger- werk verwaltungs ag, in explanation of the decision.

in a joint declaration, Dräger emphasized that the buyback would change nothing for customers: “employees from both companies will still be on hand to provide expert advice.” Dräger and Siemens will continue to invest heavily in product innova-tions in the coming years as well as develop and supply joint solutions. “we are already working closely with Siemens to successfully implement projects in a wide range of areas, integrating the technological solutions of both companies and in doing so offering additional benefits for our customers,” said Dräger, who noted, for example, that the diag nosis and therapy solutions of both companies complement each other. Dräger also identified considerable potential for joint projects with Siemens in the area of safety technology.

Dräger emphasized that medium-term investment plans will remain unchanged by the buyback: “we will implement our investments as well as our research and development budget as planned.” He also noted that the turnaround program will play a major role in reducing the company’s breakeven point and also free up funds for investments in the future. The transaction is still awaiting the approval of antitrust authorities.

Boosting group earnings for 2010: buyback of minority stake in Dräger Medical.

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Accreditation Gives Cus-tomers Added AssuranceDräger operates its own TestCenter (cf. Dräger review 96.1; pp. 28 ff.), which five years ago was awarded “accredited laboratory” status under the aegis of the german accreditation Council. This certifies that all test and documentation procedures in all seven of the center’s testing areas are conduct-ed by trained operatives in line with the latest scientific standards. “at the end of 2009, following an extensive external audit, we received a new certi- fi-cate confirming our accreditation for a further five years,” says Dr. Manfred reh, Deputy Director at the TestCenter.

This accreditation is valid worldwide and gives customers the assurance that products developed and manufactured by Dräger are tested according to the latest standards. “That’s quite some challenge, particu-larly with respect to the assessment of the bio com-patibility of the materials used in products,” reh ex-plains. Conducted every five years, the major audit is a substantial procedure and this time involved a total of seven auditors visiting Lübeck. “but it’s well worth all the effort,” says reh, “because this accreditation is accepted worldwide.”

The Dräger TestCenter ensures certified quality.

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Dräger review 99 | February 2010 7Dräger review 99 | February 2010

Faster Testing and Increased Sensitivity for THC Thanks to a new antibody-based technology, the Dräger DrugTest 5000 Test Kit now has a detection sensitivity of five nanograms of THC per milliliter of saliva. “That’s a significant advance on the previous cut-off of 25 nanograms per milliliter,” explains Dr. Stefan Steinmeyer, drug test expert at Dräger. Moreover, testing time has fallen from 12 to around eight minutes. That’s all it takes to detect THC, the active ingredient in marihuana, at a concentration equivalent to one cube of sugar dissolved in around a million liters of water. in field tests, the number of positive identifications increased by a factor of almost three compared to the previous test. “That will increase safety on the road and also in the workplace,” says Steinmeyer. in another study*, the belgian Criminological institute has also confirmed the test’s increased detection sensitivity for THC. belgium is planning new legislation this year to replace blood tests with tests using saliva samples.

Spain, too, is working on a similar law — the implementation of which is possible thanks to this highly sensitive test that is also fully suitable for use in the field. Such a test must not only function in the laboratory but also has to prove itself as part of an entire system, in series production, and, most importantly of all, in everyday operations. all of which is the case with the new test kit. Despite the significant improvements, the new product was launched without the usual fanfare, with both price and item number remaining unchanged. given that the test now meets practically any conceivable sensitivity requirements, developers are now concentrating on making it even faster.* S.M.r. wille, et al., evaluation of on-site oral fluid screening using Drugwipe-5+, rapidSTaT and DrugTest 5000 for the detection of drugs of abuse in drivers, Forensic Sci. int., 2009

Fast testing for THC: reliable results within a mere eight minutes.

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Dräger Repurchases Siemens Stakeat the end of 2009, Dräger announced that it was to buy back the 25 percent stake in Dräger Medical ag & Co. Kg held by Siemens ag, Munich. “Purchasing this stake at an acceptable price will boost group earnings in 2010. This move also reduces complexity and allows us to establish ourselves as an integrated tech - nology group,” said Stefan Dräger, Chairman of the executive board of Dräger- werk verwaltungs ag, in explanation of the decision.

in a joint declaration, Dräger emphasized that the buyback would change nothing for customers: “employees from both companies will still be on hand to provide expert advice.” Dräger and Siemens will continue to invest heavily in product innova-tions in the coming years as well as develop and supply joint solutions. “we are already working closely with Siemens to successfully implement projects in a wide range of areas, integrating the technological solutions of both companies and in doing so offering additional benefits for our customers,” said Dräger, who noted, for example, that the diag nosis and therapy solutions of both companies complement each other. Dräger also identified considerable potential for joint projects with Siemens in the area of safety technology.

Dräger emphasized that medium-term investment plans will remain unchanged by the buyback: “we will implement our investments as well as our research and development budget as planned.” He also noted that the turnaround program will play a major role in reducing the company’s breakeven point and also free up funds for investments in the future. The transaction is still awaiting the approval of antitrust authorities.

Boosting group earnings for 2010: buyback of minority stake in Dräger Medical.

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Accreditation Gives Cus-tomers Added AssuranceDräger operates its own TestCenter (cf. Dräger review 96.1; pp. 28 ff.), which five years ago was awarded “accredited laboratory” status under the aegis of the german accreditation Council. This certifies that all test and documentation procedures in all seven of the center’s testing areas are conduct-ed by trained operatives in line with the latest scientific standards. “at the end of 2009, following an extensive external audit, we received a new certi- fi-cate confirming our accreditation for a further five years,” says Dr. Manfred reh, Deputy Director at the TestCenter.

This accreditation is valid worldwide and gives customers the assurance that products developed and manufactured by Dräger are tested according to the latest standards. “That’s quite some challenge, particu-larly with respect to the assessment of the bio com-patibility of the materials used in products,” reh ex-plains. Conducted every five years, the major audit is a substantial procedure and this time involved a total of seven auditors visiting Lübeck. “but it’s well worth all the effort,” says reh, “because this accreditation is accepted worldwide.”

The Dräger TestCenter ensures certified quality.

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8 Dräger review 99 | February 2010 Dräger review 99 | February 2010

New Drugs — New StrategiesFor some people, drugs are part of daily life. but many drugs pose a health hazard to large numbers of people. Today, drugs prescribed for medical uses are iNcreaSiNgly beiNg abuSeD all over the world as “drugs” in the traditional meaning of the word. it isn’t easy to detect them — but we’re working on solutions to this problem.

a baNkNote’S “career” in the underworld of illegal drugs can be easi-ly detected if you only examine it close-ly enough. “Almost all of the banknotes that have been in circulation for a while have traces of cocaine sticking to them,” says Hans-Jürgen Maurer, who works at the State Institute for Preventive Action in the German state of Saarland. For that, a clean banknote only needs to briefly lie in a supermarket cash register next to anoth-er one that has been used to snort pow-dered cocaine. The amount of cocaine that sticks to the second banknote is not enough to cause a high, but it’s enough to be detected by the ultramodern meth-ods used by narcotics agents.

This example shows how thoroughly our everyday lives have been penetrated by drugs — not to mention alcohol, cigarettes, and the substances doctors call “everyday drugs,” namely coffee and tea. The use of consciousness-altering substances has been an inextricable part of human histo-ry for thousands of years. The oldest writ-ten documents testifying to that are 8,000 years old, and the Bible tells us that Noah was the inventor of winemaking.

every society has a favorite drug

According to the World Drug Report 2009 of the United Nations Office on Drugs and Crime (UNODC), alcohol is consumed at about the same rate in every country of the world, whereas cocaine-like substan-ces dominate in North and South Ameri ca. Cannabis products are consumed primar-ily in Africa and the South Pacific region. And opiates are intoxicating the rest of the world, except for countries like Japan and

Sweden, where amphetamines are the drug of choice. According to the UNODC, between 172 and 250 million people con-sumed drugs last year, and this consump-tion became a problem for 18 to 38 mil-lion of them. These figures don’t even include alcohol, which is solely responsi-ble for 85 percent of all drug problems.

Drugs have consequences

Even though people all over the world have different views about where to draw the line between legal and illegal drugs, all cultures are aware of the destructive consequences of drug consumption, not only for the consumers but also for the people around them. Alcohol and other drugs are a risk factor on the road and in the workplace. According to statistics col-lected by the German Centre for Addiction Issues, about three quarters of employees in Germany engage in the “low-risk con-sumption” of alcohol. Between two and three percent of employees are addicted to alcohol, and ten percent consume it to a degree that puts them at risk of addiction. The resulting costs due to loss of produc-tivity in the workplace (through absentee-ism and mistakes) amount to billions of euros in Germany alone. Even more prob-lematic is the increased risk of accidents. Every company bears responsibility for the health of its employees. This means it must protect its employees from the con-sequences of substance abuse. In most countries, works agreements determine whether, when, and how employers are permitted to conduct spot checks. In some sectors it’s already customary for job applicants to provide a blood sample

when they are hired, and in safety-rele-vant jobs these samples may be analyzed to identify substance abuse.

German legislation has drastically limited the possibilities for monitoring substance use in the workplace through medical examinations of employees. Health and safety in the workplace must be balanced against employees’ personal rights. This balancing process leads to the conclusion that personal rights have pre-cedence. This is why such a test requires the individual’s written consent. Labor law specialists point out that job appli-cants can theoretically refuse to take such tests. However, another topic frequently discussed by company lawyers and labor courts is the question of how voluntary the signature of a statement of consent actually is if the candidate is afraid that a refusal would work to his or her disad-vantage in the selection process. Recently a number of major companies and radio broadcasters operating under public law were criticized by the German media and elsewhere because they required job appli-cants to submit blood samples.

For a long time now, a major chem-icals company has conducted drug screening whenever one of its employ-ees is transferred to a safety-related posi-tion. Seven percent of these screenings indicated drug use. For Dräger compa-ny doctor Frank Ensslen it’s clear that the results of such examinations of pro-spective and actual employees may not leave the premises of the responsible physician. That’s forbidden by the prin-ciple of physicians’ confidentiality. Some experts are now arguing that this issue >

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The workplace Focus

New Drugs — New strategiesFor some people, drugs are part of daily life. but many drugs pose a health hazard to large numbers of people. Today, drugs prescribed for medical uses are iNcreasiNgly beiNg abuseD all over the world as “drugs” in the traditional meaning of the word. it isn’t easy to detect them — but we’re working on solutions to this problem.

First blow, then go: For drivers like this locomo-tive engineer in sweden, this is a completely normal safety procedure which protects passengers and freight.

when they are hired, and in safety-rele-vant jobs these samples may be analyzed to identify substance abuse.

German legislation has drastically limited the possibilities for monitoring substance use in the workplace through medical examinations of employees. Health and safety in the workplace must be balanced against employees’ personal rights. This balancing process leads to the conclusion that personal rights have pre-cedence. This is why such a test requires the individual’s written consent. Labor law specialists point out that job appli-cants can theoretically refuse to take such tests. However, another topic frequently discussed by company lawyers and labor courts is the question of how voluntary the signature of a statement of consent actually is if the candidate is afraid that a refusal would work to his or her disad-vantage in the selection process. Recently a number of major companies and radio broadcasters operating under public law were criticized by the German media and elsewhere because they required job appli-cants to submit blood samples.

For a long time now, a major chem-icals company has conducted drug screening whenever one of its employ-ees is transferred to a safety-related posi-tion. Seven percent of these screenings indicated drug use. For Dräger compa-ny doctor Frank Ensslen it’s clear that the results of such examinations of pro-spective and actual employees may not leave the premises of the responsible physician. That’s forbidden by the prin-ciple of physicians’ confidentiality. Some experts are now arguing that this issue >

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Focus The workplace


should be treated as a matter of work safety. “We can help addicts only if we can identify them — that way we’ve got a starting point for a discussion,” Ensslen says. He adds that a bigger problem is posed by employees who come to work in the morning with residual alcohol in their bloodstream and sit down too ear-ly behind a steering wheel or at the con-trols of an industrial machine: “Most of them don’t realize how slowly alcohol is metabolized.” The best protection cur-rently available is monitoring by means of minimally invasive methods such as a breathalyzer or a oral fluid test. “One sure method of prevention could be the introduction of zero-tolerance rules in the workplace, combined with agreed-upon monitoring,” says Dr. Stefan Stein-meyer, who is responsible for the busi-ness development of drug detection systems at Dräger. For example, occu-pational safety officers could use alcohol detection devices to monitor employees quickly and reliably. Automatic access controls have long been established for a number of hazardous jobs, for example in Australia. “In order to enter the work-station, the employee first has to blow into a breathalyzer,” says Steinmeyer.

Driving only after an alcohol test

For this purpose, Dräger launched the Interlock XT on the market (see also Dräger Review 91 and 94). This is known as an “alcohol interlock” which is con-nected with the electronic starting mech-anisms of vehicles and machines. The motto here is “First blow, then go!” After the driver sticks the key into the igni-

tion, these built-in devices ask the driv-er to provide a breath sample. He or she must blow into an integrated breatha-lyzer which determines the alcohol con-tent within seconds. Only if the driver is sober does the device permit the vehi-cle to be started. The breathalyzer reg-isters the user’s every individual breath and can also detect attempts to falsify the results by blowing in air from a balloon or through a long hose inside which the alcohol is expected to condense. The inter-locks could also theoretically be used at gate controls in the food industry or in hospitals, at industrial rollers and press-es, or to govern access to areas where an employee incapacitated by alcohol could pose a danger to life and limb.

It’s very clear that the systems used in such sensitive areas must function with absolute reliability rather than, for exam-ple, blocking a machine simply because the user has just eaten an apple. False pos-itives must be ruled out in the case of dia-betes patients or people who are fasting; in both cases, the body generates substanc-es that the electronic measuring device should not confuse with alcohol. For the extremely unlikely case of a total failure of the system, some freight forwarders even build in an emergency switch that tem-porarily overrides the electronic blocking mechanism.

sweden is the pioneer

Dr. Johannes Lagois, a specialist in the Alcohol Interlocks business area at Dräger, believes there are two crucial applications for these devices today. The first of these is in the area of preven-

DrugTest 5000 (left) provides reliable measuring results in three steps, even under difficult environ-mental conditions. on the right is Alcotest 7510.

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tion, these built-in devices ask the driv-er to provide a breath sample. He or she must blow into an integrated breatha-lyzer which determines the alcohol con-tent within seconds. Only if the driver is sober does the device permit the vehi-cle to be started. The breathalyzer reg-isters the user’s every individual breath and can also detect attempts to falsify the results by blowing in air from a balloon or through a long hose inside which the alcohol is expected to condense. The inter-locks could also theoretically be used at gate controls in the food industry or in hospitals, at industrial rollers and press-es, or to govern access to areas where an employee incapacitated by alcohol could pose a danger to life and limb.

It’s very clear that the systems used in such sensitive areas must function with absolute reliability rather than, for exam-ple, blocking a machine simply because the user has just eaten an apple. False pos-itives must be ruled out in the case of dia-betes patients or people who are fasting; in both cases, the body generates substanc-es that the electronic measuring device should not confuse with alcohol. For the extremely unlikely case of a total failure of the system, some freight forwarders even build in an emergency switch that tem-porarily overrides the electronic blocking mechanism.

Sweden is the pioneer

Dr. Johannes Lagois, a specialist in the Alcohol Interlocks business area at Dräger, believes there are two crucial applications for these devices today. The first of these is in the area of preven-

tion, to keep individuals from operating vehicles or machines if they’ve drunk too much alcohol. In Sweden approxi-mately 40,000 buses, trucks, and taxis are equipped with breathalyzers. “Some local authorities now award transport contracts to school bus operators only if the buses have built-in breathalyz-ers,” says Lagois. The Swedish parlia-ment even briefly discussed the possi-bility of building interlocks into every car in order to finally reduce the num-ber of traffic accidents due to alcohol. In Austria as well, freight forwarders are already building such devices into their trucks, in line with strict regulations. If a device registers an attempt by the driver to operate a vehicle while under the influence of alcohol or to trick the device, the freight forwarding compa-ny is notified of the violation and it then sends a warning to the driver. If there is a second violation, the driver can be immediately fired.

According to Lagois, the second major area of application for alcohol interlocks is in programs for people convicted of drunk driving. “In the U.S., about 180,000 drivers are required to use such devices at least temporarily,” he says. In his opinion, these systems could also help the Euro-pean Union to reach its goal of cutting in half the number of traffic fatalities, from 50,000 in 2001 to 25,000 in 2010. In Sweden, a pioneer in this field, sever-al hundred private cars have already been equipped with interlocks, and a similar pilot program is being set up in the Neth-erlands. “People in Germany are still skep-tical. Here they’ve established the Med-

ical-Psychological Assessment, which evaluates a person’s ability to drive after he or she has been convicted of drunk driving,” says Lagois, adding that in Ger-many the legal status of such electronic immobilizers has not yet been clarified.

A log is included

However, after an Medical-Psychological Assessment it’s never completely certain whether the problem has really been solved. “In a third of the cases we can be fairly certain that they’ll never again drive a vehicle while drunk,” says Lagois. “With another third, it soon becomes clear that they’ll do it again. But as for the rest, it’s not clear whether they’ve merely per-suaded the assessor that they’ve kicked the habit.” Thanks to the interlocks, one can simply check to see how the client behaves and take remedial measures if necessary. Plans call for pilot programs to be launched next year in Germany as well. In countries including the U.S., Dräger offers, in addi-tion to the breathalyzer and a connected device to monitor the process of starting the vehicle, a “log” of the behavior of indi-viduals who are under observation.

The drivers in this category must go to a service station every two months and have the data in their logs read out. The data is then sent via secure connections to a protected server for analysis. The system can generate reports automatically and send them to the responsible authority. According to Lagois, it would even be con-ceivable for the data to be sent to a cen-tral server in real time via mobile radio. However, in order for that to happen a legal framework must be in place. Lagois

Measuring devices with higher precision offer reliable additional benefits

>



doesn’t think there’s much technical lee-way left when it comes to monitoring the alcohol content of people’s breath. But he estimates that in ten years there might be interlock systems on the market that also test for the presence of other drugs. “It has been possible for more than 60 years to measure the amount of alcohol in an individual’s breath, but only in the past few years have we developed methods of identifying amphetamines, opiates or cannabinoids in a person’s saliva within minutes. Police departments want to have a test for drugs that works just as quick-ly and reliably as tests for alcohol,” says Hans-Jürgen Maurer, Chief Police Super-intendent of the German state of Saar-land, who works in the State Institute for Preventive Action and is recognized as one of the pioneers in the area of drug identi-fication in road traffic.

Antibodies on the lookout for drugs

“The DrugTest 5000 can identify most of the known illegal drugs and even unknown ones, because it recognizes family resemblances between these substances rather than each individual substance,” explains Dr. Stefan Stein-meyer. Unlike the electrochemical sen-sor used to detect alcohol in a person’s breath, the immunological drug tests use antibodies to identify the illegal substances, and they then make these substances visible by inducing a color reaction. Immunological drug tests origi nated in the U.S., where “immuno-assays” for drug detection have been used extensively since the late 1980s in physi-cal examinations of job candidates and

for monitoring drug-free conditions in the workplace. An immunoassay requires a bit more time than the sensor used for alcohol, which also provides quantitative data. By contrast, the antibodies used in the saliva test identify the basic chemical structure of the drugs and thus can also detect chemical “cousins” of the origi-nal target molecules; the experts call this “cross-sensitivity.”

However, it’s almost impossible to quantify the amount of drugs present via this method; above a predefined thresh-old value, it is merely possible to indi-cate the presence of a drug. Those who want more precise details must there-fore bring the sample to a laboratory and send it through a gas or liquid chro-matograph that separates it into all of its components. These components are then identified by a downstream mass spectrometer by means of their molecu-lar weight. Dräger offers such analyses as a service to public authorities and detoxi-fication clinics. Shipping companies also use this service. DrugTest 5000 can iden-tify even medications classed as tranquil-izers (see also Dräger Review 96, p. 8 ff.). Like alcohol, the benzodiazepines har-bor tremendous potential for addiction and pose hazards in road traffic and at the workplace because they alter the users’ awareness and slow down their reaction times.

Doping: a wave of new drugs

The experts are already seeing a wave of new drugs approaching the workplace. According to a study conducted by the health insurer DAK, in Germany alone

two million people occasionally use pills and other medications to enhance their work performance, and approximately 800,000 people do so regularly. These doping substances often include medica-tions meant for people with depression, dementia or hyperactivity. Such sub-stances, including psychopharmaceuti-cals, are frequently encountered in the medical context in particular, because they are more easily accessible there. In Germany, for example, among the peo-ple insured by the statutory health insur-ance companies are about 1.4 million individuals who are addicted to medica-tions prescribed by doctors.

Searching for traces with a brush

As a consequence of a verdict handed down in 2006 by the Hamburg Labor Court, random drug tests may soon be carried out more often in the workplace as well. The court supported a compa-ny that had submitted its employees in a container terminal to random drug tests in conformity with a works agreement. The court concluded that the personal rights of the plaintiff had been affected but not violated, and that the infringe-ment of his personal rights through the drug test was commensurable and there-fore permissible, because the plaintiff’s tasks were associated with considerable hazards. In the court’s opinion, the pur-pose of the test was not to establish drug addiction but to determine the plain-tiff’s current ability to do his work.

Maurer, the drug expert, is plan-ning to conduct a pilot project soon in a somewhat less hazardous work-

place — an educational institution in the Saarland area of Germany. As part of the project he will wipe off the door handles of the institute with a cloth for sample collecting and then wash the sam-ple collection device. This mixture, in place of a saliva sample, will then be sub-mitted to the DrugTest 5000. “We first want to establish whether addictive sub-stances are present; if they are, we can then consider what countermeasures we want to take,” he says. Maurer con-siders it important not to “go hunting” for individuals violating the rules. He believes that employers have a responsi-bility toward their employees to counter potential drug abuse by means of appro-priate informational programs.

Maurer does not yet know what to expect from his experiment with the doorknobs of the educational institu-tion. He may find cocaine, as did other researchers two and a half years ago in the ambient air of La Sapienza Univer-sity in Rome. But even if that happens, it would still not be clear whether the drug was transferred to the doorknob direct-ly from the hand of a user or via a taint-ed banknote. It may be possible to reach such a conclusion from the amounts involved. In any case, after the investi-gation the doorknobs and other surfaces will be very clean. That might be good for the banknotes — it would surely give the concept of “money laundering” a whole new meaning. Hanno Charisius

Two million people in Germany are abusing prescription medications

>

Further information online, including: substance abuse and diagnostics

www.draeger.com/99/diagnostics



The workplace Focus

two million people occasionally use pills and other medications to enhance their work performance, and approximately 800,000 people do so regularly. These doping substances often include medica-tions meant for people with depression, dementia or hyperactivity. Such sub-stances, including psychopharmaceuti-cals, are frequently encountered in the medical context in particular, because they are more easily accessible there. In Germany, for example, among the peo-ple insured by the statutory health insur-ance companies are about 1.4 million individuals who are addicted to medica-tions prescribed by doctors.

searching for traces with a brush

As a consequence of a verdict handed down in 2006 by the Hamburg Labor Court, random drug tests may soon be carried out more often in the workplace as well. The court supported a compa-ny that had submitted its employees in a container terminal to random drug tests in conformity with a works agreement. The court concluded that the personal rights of the plaintiff had been affected but not violated, and that the infringe-ment of his personal rights through the drug test was commensurable and there-fore permissible, because the plaintiff’s tasks were associated with considerable hazards. In the court’s opinion, the pur-pose of the test was not to establish drug addiction but to determine the plain-tiff’s current ability to do his work.

Maurer, the drug expert, is plan-ning to conduct a pilot project soon in a somewhat less hazardous work-

place — an educational institution in the Saarland area of Germany. As part of the project he will wipe off the door handles of the institute with a cloth for sample collecting and then wash the sam-ple collection device. This mixture, in place of a saliva sample, will then be sub-mitted to the DrugTest 5000. “We first want to establish whether addictive sub-stances are present; if they are, we can then consider what countermeasures we want to take,” he says. Maurer con-siders it important not to “go hunting” for individuals violating the rules. He believes that employers have a responsi-bility toward their employees to counter potential drug abuse by means of appro-priate informational programs.

Maurer does not yet know what to expect from his experiment with the doorknobs of the educational institu-tion. He may find cocaine, as did other researchers two and a half years ago in the ambient air of La Sapienza Univer-sity in Rome. But even if that happens, it would still not be clear whether the drug was transferred to the doorknob direct-ly from the hand of a user or via a taint-ed banknote. It may be possible to reach such a conclusion from the amounts involved. In any case, after the investi-gation the doorknobs and other surfaces will be very clean. That might be good for the banknotes — it would surely give the concept of “money laundering” a whole new meaning. Hanno charisius

old acquaintances — or the “new drugs” The “new drugs” include substances used to combat illness — or abused to enhance mental performance or induce a state of intoxication. examples:u Galantamin To combat dementia due to an acetylcholine deficiency — or to strengthen the memoryu Donepezil To treat mild to middling levels of forgetfulness — or to enhance memory and cognitionu Modafinil To combat the sleeping sickness known as narcolepsy — or to enhance attention and memoryu Prozac (active ingredient: fluoxetin) an antidepressant also used in cases of obsessive-compulsive behavior and panic attacks — or to brighten up the user’s moodu Benzo diazepines Tranquilizers used to treat restlessness, anxiety, and sleepless-ness, and as emergency drugs in cases of epileptic seizure — or as intoxicantsu Rivastigmine Medication used for alzheimer patients — or to enhance memoryu Methylphenidate (e.g. ritalin) Medication for patients with attention Deficit/hyperactivity Disorder (aDhD) — or for enhancing concentration, performance, and decision-making ability and suppressing fatigueu spice and similar products No medical indication; mixtures of spices and herbs enhanced with chemically produced drugs are illegal drugs

Further information online, including: substance abuse and diagnostics

www.draeger.com/99/diagnostics

Drug consumption throughout the world

opiates cannabis cocaine Amphetamines others No data available

N.Amerika

Süd Amerika

Europe

Afrika

Asia

Oceania

North America

20.7%

17.8% 33.5%

23.3%

4.7%

south America

N.Amerika

Süd Amerika

Europe

Afrika

Asia

Oceania

10%

52.1%33.2%

3.1%

1.7 %

N.Amerika

Süd Amerika

Europe

Afrika

Asia

Oceania

Africa

5.1%

62.8%16.5%

8.4%

7.2 %

N.Amerika

Süd Amerika

Europe

Afrika

Asia

Oceania

oceania

19.8%47%

26.3%

6.5%0.4%cocaine

N.Amerika

Süd Amerika

Europe

Afrika

Asia

Oceania

Asia

10%

64.6%17.8%

0.3%cocaine

7.4%

N.Amerika

Süd Amerika

Europe

Afrika

Asia

Oceania

Europe

10.9%

59.7%19.5%

1.5%8.4%

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14 Dräger review 99 | FebruarY 2010

RepoRt Fire Protection

Dräger review 99 | FebruarY 2010

surements of so-called indicator substanc-es make it possible to estimate the fumes’ toxicity. Such substances also include car-bon monoxide, hydrogen chloride (HCl, hydrochloric acid gas), and methanal (CH2O, formaldehyde) as well as HCN.

As fumes continuously change both their composition and concentration, a single simultaneous measurement can-not provide a reliable determination of the fumes’ overall toxicity. “Instead, it is necessary to analyze the gas mixture repeatedly, at different measurement locations,” recommends Stefan Denker from Dräger, who is a member of Section 10 of the vfdb — the German Fire Protec-tion Association — which concerns itself with various topics related to the detec-tion of hazardous substances. The prima-ry objective of a series of measurements is to determine the medium-term expo-sure and possible trends in the composi-tion of the smoke gases and their propaga-tion. The tolerance values of currently 44 toxic substances for firefighting missions (ETW) which were published in the vfdb directive 10/01 are currently authoritative for the evaluation of measurement results with regard to the endangerment of oper-ational personnel and residents in Germa-ny. These values refer fundamentally to acute toxic effects, and that distinguish-es them from the limit values for long-term exposure such as the OEL (occupa-tional exposure limit) and the threshold limit values (TLV) published by the Amer-ican Conference of Governmental Indus-trial Hygienists (ACGIH).

Dräger has drafted strategy sugges-tions based on vfdb directives 10/01 and

10/05-T1 to T3 for firefighting servic-es to evaluate measured toxic substance concentrations during operations. The parameters determining which measur-ing technology is selected are the need for fast and reliable results, the low concen-trations that are frequently encountered, the wide range of substances to be mea-sured, and the harsh operational condi-tions. The strategy suggestion comprises a basic measurement scenario for indi-cator substances in fire gases (CO, HCN, HCl, NOx, and CH2O) and three simulta-neous tests which are more strongly dif-ferentiated according to the type of oper-ation. When Dräger-Tubes are used, these three tests, which result in a total of 15 determinations, can be carried out in less than 15 minutes. These simultane-ous tests are complemented by, for exam-ple, the electrochemical measurement of the O2 concentration and the Ex measure-ment using catalytic sensors.

Global adaptation

The ETW tolerance values have been regularly calibrated against the inter-national acute exposure guideline lev-els (AEGL), which are drawn up by the U.S. Environmental Protection Agency in cooperation with many countries and organizations (including firefighting ser-vices). The AEGL-2 values for four-hour exposure are adopted here — always pro-vided that the substance is relevant to firefighting operations and can be mea-sured on site using conventional meth-ods. The global adaptation of the limit values makes sense because the mean-ing of the indicator substances is simi-

Dangerous Cocktailthe overall toxicity of the cocktail of hazardous substances contained in fumes can be estimated by measuRinG inDiCatoR substanCes such as hydrocyanic acid or carbon monoxide. international standards exist for measurement strategies and the guide values for interpreting the results.

lar in the firefighting services’ techni-cal analysis in different countries. Rick Wanek, an expert on portable gas detec-tion equipment at Dräger, confirms this, using North America as an example. The decisive factors for selecting a system are its ease of operation and maintenance and its cost-effectiveness. Dräger-Tubes, which are calibrated for their entire ser-vice life, remain widely used today, espe-cially for follow-up work after the fire has been extinguished. However, the trend in continuous measuring equipment for use during firefighting operations is toward electrochemical sensors. peter thomas

HyDRoCyaniC aCiD (hydrogen cyanide, HCN) is one of the most toxic fumes. Compared to carbon monoxide (CO), the toxicity of the same quantity of hydrogen cyanide is 20 times higher. At the same time, the proportion of HCN in fumes is increasing. A study by Yves Alarie (“Toxicity of fire smoke”; Critical Reviews in Toxicology, 2002; 32(4):259–89) found that 87 percent of the fire fatalities stud-ied showed toxic levels of HCN in their blood. Alarie suggested that the cause of this was the continual increase in the quantity of synthetic polymers in everyday use since the middle of the 20th century. The thermal decomposition of these plas-tics in particular in fires produces HCN. Extremely high HCN concentrations are recorded in fires in the waste disposal, plastics, and packaging industries. Continually measuring

Firefighting personnel cannot avoid the use of heavy breathing apparatus when fighting fires. And for rescue operations to save people, there are fire escape hoods such as the Dräger PARAT C, which pro-vides 15 minutes of protection against dangerous fumes. But firefighting per-sonnel and residents at greater distanc-es from the fire can also be endangered by clouds of fumes. And greater caution is also required when the firefighters are carrying out subsequent work with-out the use of breathing apparatus on the site of the fire after it has cooled down, as the danger of toxic gas emissions is still present. Continual analysis therefore is standard procedure in many firefighting operations. Multiple simultaneous mea- P

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14-15_Blausäure_S 14 20.01.2010 12:29:24 Uhr

Dräger review 99 | FebruarY 2010 15Dräger review 99 | FebruarY 2010

10/05-T1 to T3 for firefighting servic-es to evaluate measured toxic substance concentrations during operations. The parameters determining which measur-ing technology is selected are the need for fast and reliable results, the low concen-trations that are frequently encountered, the wide range of substances to be mea-sured, and the harsh operational condi-tions. The strategy suggestion comprises a basic measurement scenario for indi-cator substances in fire gases (CO, HCN, HCl, NOx, and CH2O) and three simulta-neous tests which are more strongly dif-ferentiated according to the type of oper-ation. When Dräger-Tubes are used, these three tests, which result in a total of 15 determinations, can be carried out in less than 15 minutes. These simultane-ous tests are complemented by, for exam-ple, the electrochemical measurement of the O2 concentration and the Ex measure-ment using catalytic sensors.

Global adaptation

The ETW tolerance values have been regularly calibrated against the inter-national acute exposure guideline lev-els (AEGL), which are drawn up by the U.S. Environmental Protection Agency in cooperation with many countries and organizations (including firefighting ser-vices). The AEGL-2 values for four-hour exposure are adopted here — always pro-vided that the substance is relevant to firefighting operations and can be mea-sured on site using conventional meth-ods. The global adaptation of the limit values makes sense because the mean-ing of the indicator substances is simi-

Dangerous CocktailThe overall toxicity of the cocktail of hazardous substances contained in fumes can be estimated by measurinG inDiCaTOr subsTanCes such as hydrocyanic acid or carbon monoxide. international standards exist for measurement strategies and the guide values for interpreting the results.

a combination of poisonsCO and HCN contribute to smoke poisoning. However, they have different effects. CO blocks the binding of oxygen to the hemoglobin in the erythrocytes and thus interrupts the O2 absorption of the blood circulation. The cyanide ions of HCN bind to the cytochrome c oxidase in the mitochondria and thus block cellular respiration. The combined intoxication by both substances is particularly dangerous, as previous methods of treatment for HCN poisoning could only be applied within limits when CO poisoning was also present. This situation has now changed, thanks to the avai la bility of the antidote Cyanokit with the active ingredient hydroxocobalamin, which can also be administered in the presence of CO poisoning.

Scientists in North america are currently researching better methods of estimating the combined toxic effects of different hazardous substances in smoke gases. Here too, the main target of this work is the combination of HCN and CO, which the american toxicologist David g. Penney has dubbed the “toxic twins.”

lar in the firefighting services’ techni-cal analysis in different countries. Rick Wanek, an expert on portable gas detec-tion equipment at Dräger, confirms this, using North America as an example. The decisive factors for selecting a system are its ease of operation and maintenance and its cost-effectiveness. Dräger-Tubes, which are calibrated for their entire ser-vice life, remain widely used today, espe-cially for follow-up work after the fire has been extinguished. However, the trend in continuous measuring equipment for use during firefighting operations is toward electrochemical sensors. Peter Thomas P

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minimizing the danger posed by fumes of

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14-15_Blausäure_S 15 20.01.2010 12:29:33 Uhr


His area of operation is as large as the city of Munich — includ-ing the Bavarian capital’s incorporated communities — yet it can’t be seen from an airplane. Dieter Wendrich, an elec-trical engineer, works underground. He’s the head of the mine rescue team at the Hattorf-Wintershall mine in K+S KALI GmbH’s Werra plant. His station house is a crystal palace 1,000 meters below the surface of the earth. The walls sparkle with the potash and salt that are mined here and for which the compa-ny is named.

Wendrich and his roughly 70-mem-ber team have duties underground that are similar to those of a fire department above ground. The demands on each and every individual may be even higher, however: Every piece of equipment must be in place and ready to use, deployment routes are often very long, and even with the best of training, potential hazards are even more unpredictable than they are above ground. On top of it all, Wendrich and his crew don’t just respond to emer-gencies — they are also involved in nor-mal daily mining operations.

Warm and well-ventilated

Anyone taking the barely two-minute ride in the cage down the 700-meter-deep shaft will see that the mine is pret-ty much like a normal workplace. There are broad, surfaced, and lighted roads (drifts) and traffic signs. Roughly 730 vehicles and machines are designed for the low drift height (which is generally only two meters). The air in the mine is not thick with exhaust despite the large

protection for the Underground CityWorking Conditions at depths of 1,000 meters or more are very unusual. That’s also true for the fire departments — called mine rescue teams — that are an integral part of the mining process.

Underground: Miners refer to the extraction of potash as “parlor mining,” since potash, unlike coal, is white instead of black.

number of diesel vehicles. “We venti-late the mine with 66,000 cubic meters of fresh air — per minute,” explains Wendrich. The temperature here is 24 degrees Celsius. Down deeper, it climbs to a temperature more reminiscent of the dog days of summer — roughly 34 degrees Celsius.

Despite all the technology available today, miners still have a very demand-ing workplace. Although machines and explosives make the work easier, under-ground mining still saps your strength. Added to this are noise, dust, and the lack of a view of the outdoors. These are all stresses that explain why the age limit for miners working underground is set at 60. “Even though what we do here is ‘par-lor mining’ compared to hard coal min-ing,” adds Wendrich. True enough — it isn’t black and dirty down in the potash and salt mine, but you do taste the salty bitterness of the dust on your lips.

Miners working in three shifts extract more than 60,000 tons of crude salt a day here. Martin Wagner, head of Pro-duction and Technology at the Hattorf-Wintershall mine, explains exactly how this is done. We ride in an open SUV the lower 300 meters to the face — the end of the drift, in other words — from which mining tunneling continues. We sit on a rearward-facing bench mounted on the bed of a pickup, dressed, of course, in miner’s clothes, safety shoes, helmet, and lamp. The Oxy K 50 S oxygen self-res-cuer, which is automatically registered upon driving into a lock, is close at hand. The roof and the walls flash by. “It only looks that fast,” calls Wagner over the

16-19_K+S_S 16 20.01.2010 12:08:26 Uhr


unDergrounD Mining RepoRt

protection for the Underground CityWoRking Conditions at depths of 1,000 meters or more are very unusual. That’s also true for the fire departments — called mine rescue teams — that are an integral part of the mining process.

slipstream and the noise, “because we’re so close to them as we drive by!” Wagner explains the structure of the mine on the drive to the face: “It’s like a chessboard.” The potash is extracted using a grid of parallel and perpendicular drifts. The grid size depends on the depth, the thick-ness of the seam, and the type of salt. The grid size is 45 x 45 meters. The drifts are 15 meters wide; the pillars, 30 meters. The tunnel along which we are riding ris-es and falls. “We’re following the course of the potash deposits,” explains Wagner. “Due to faults and upfolding, they aren’t horizontal.” The underground road net-work therefore includes grades that can be as steep as 16 percent.

patterned blasting

At the end of the drive we stand in front of the brightly illuminated face, in front of which is the carriage with the seven-me-ter-long drill. Extraction begins with the drilling of three adjacent cut holes using this drill, which measures 280 millime-ters in diameter. Blastholes with substan-tially smaller diameters are then drilled in a specific pattern around the cut holes. “That’s all done automatically,” says Wag-ner. “The ‘drill pattern’ is precisely tar-geted toward an endpoint, using an auto-mated system, among other things.”

And that’s just about it for this shift in the shaft. Trained blasters blow an explosive into the holes. It is ignited at the end of the shift. For maximum effect, the holes in the drill pattern are ignit-ed according to a specific time schedule, beginning with the blastholes directly adjacent to the three cut holes. Blasting > P

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(scaling) before it is secured with expan-sion bolts measuring up to 1.8 meters in length. “The roof is made up of layers,” explains Wendrich, “and bolts placed at regular intervals secure the roof and turn it into an extremely stable package.” Think of it as a leaf spring. Each of the bolts placed in a 2 x 2 meter grid supports a weight of 14 tons. That will hold, but the roof is continuously monitored nev-ertheless, both with radar and manually using so-called “sensor hooks.”

Hauling can then begin using a shovel loader that carries twelve tons of crude salt to the crusher. The driver dumps the crude salt onto a pile, from which a chain conveyor continuously feeds the crusher. The crusher grinds the crude salt down to a maximum size of roughly 200 millimeters, which is suitable for belt transport. Belt convey-ors several kilometers in length carry the crude salt on — from the shaft to the fac-tories above ground, which process the crude salt in continuous 24-hour opera-tion. Left over is two-thirds tailings, which is dumped onto piles bearing such names as “Kilimanjaro.” Only the first third is valuable — it is processed into a variety of products, primarily fertilizer (see box). On our return trip underground we pass workshops where, among other things, the meter-high tires are put onto the wheeled loaders, before we finally reach the main station of the mine rescue team. Wendrich and his colleagues demon- strate one of the self-designed emergen-cy vehicles. “You can’t buy something like this,” he says as he pulls draw-ers out of the flat superstructure and

Underground control rooms are not much different from those above ground, but much of the firefighting equipment is made in-house or specially commissioned. For example, the fire truck on the left has a low body so that it won’t scrape against the roof.

Good planning, inspections, preparations, and practice runs ensure quick assistance in emergencies underground. And that can be critical given that unpleasant surprises are commonplace enough at a depth of 1,000 meters.

> is conducted three times a day: 5:20 a.m., 1:20 p.m., and 9:20 p.m. The next shift then starts extracting the crude salt.

Despite exploratory holes, nobody knows exactly which gases the blasting has released. Irregularities are contin-uously monitored in the mining opera-tions control room via stationary mea-suring devices. After the blasting gases have dissipated, the responsible supervi-sor takes an exploratory drive with a mul-tigas measuring instrument such as the Dräger X-am 7000 before the start of nor-mal operations. As Dieter Wendrich, head of the mine rescue team, explains, blast-ing occasionally contaminates work areas with harmful gases. Miners must then use heavy respiratory protection from Dräger, such as the PSS BG 4 plus or its predecessor, the BG 174, to drive along the panels and repair them.

Carbon dioxide is unpredictable

The primary hazard in the Werra potash district is CO2. This is normally dissolved in minerals, but can be released in large quantities following blasting — either in the form of a “lake” or frozen as a result of expansion cooling. “It’s like when you quickly open a bottle of mineral water that’s been shaken up,” says Wendrich. The prevailing forces during the explo-sive release of CO2 are tremendous. He shows photographs in which mangled equipment weighing tons has been scat-tered through the drifts like toys.

Work to secure the tunnel can only begin once the all-clear has been given by the mine rescue team. A “roof scal-er” first scrapes loose stone from the roof

shows the turret on which the extended- duration respiratory protective devices are stacked.

Expertise and camaraderie

Down here you get a really good impres-sion of the team members’ camaraderie and expertise. “Everyone here has had a year of probation before he’s accepted into the mine rescue team,” says Wen-drich, who considers not only the appli-cants’ qualifications as electricians or welders, for example, but also their abili-ty to handle physical strain and get along with the team. People must be complete-ly dependable underground, and “every-thing has to be planned in such a way that it’s three times as safe as necessary,” says Wendrich. Applicants who have already worked in a rescue team above ground are more likely to be accepted, although even

Despite exploratory holes, nobody knows exactly which gases are released

Breathing equipmentalthough one can generally breathe nor mal ly underground, miners always carry self-rescuers in case of an emergency and breathing equipment in places where it’s needed. Through out the world, e.g., two Dräger products provide state-of-the-art safety. The Oxy K escape equipment (left) uses chemically bound oxygen so that miners do not have to breathe in the ambient air. Depending on the version in question, the devices supply oxygen for 30 or 50 minu tes. They are equipped with a mouth-piece, nose clamp, and protective goggles. The PSS BG 4 plus (right) is the most advanced version of Dräger’s closed-circuit breathing equipment. it lets users breathe for up to four hours in toxic environments. The PSS bg 4 plus has an integrated cooling system, is contained in an ergo no- mically shaped carrying frame, and is a well-balanced system that is comfortable to carry. because the apparatus is a closed-circuit system, the absorber binds the carbon dioxide contained in the ex-haled air, while the respiratory air comes from the oxygen tank.

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unDergrounD Mining RepoRt

untertagebau RepoRt

that is no guarantee that they will meet the rigorous demands put on prospective members of the mine rescue team.

Despite the fact that the mines are pro-vided throughout with a comprehensive and preventive fire protection system that includes more than 2,000 fire extinguish-ers (which the mine rescue team also maintains), fires do break out occasion-ally. Wendrich remembers an incident when “the hydraulic oil ignited in a vehi-cle, even though it had an onboard extin-guishing system. The tires were still smok-ing three days later.” In addition to water, which is transported in a 6,000-liter tank truck, the mine firefighters also use foam. In some cases, the mine rescue team also has to employ indirect methods to fight fires, such as blocking off long stretches of the drifts around the fire so that it no lon-ger has access to fresh air, i.e. oxygen.

(scaling) before it is secured with expan-sion bolts measuring up to 1.8 meters in length. “The roof is made up of layers,” explains Wendrich, “and bolts placed at regular intervals secure the roof and turn it into an extremely stable package.” Think of it as a leaf spring. Each of the bolts placed in a 2 x 2 meter grid supports a weight of 14 tons. That will hold, but the roof is continuously monitored nev-ertheless, both with radar and manually using so-called “sensor hooks.”

Hauling can then begin using a shovel loader that carries twelve tons of crude salt to the crusher. The driver dumps the crude salt onto a pile, from which a chain conveyor continuously feeds the crusher. The crusher grinds the crude salt down to a maximum size of roughly 200 millimeters, which is suitable for belt transport. Belt convey-ors several kilometers in length carry the crude salt on — from the shaft to the fac-tories above ground, which process the crude salt in continuous 24-hour opera-tion. Left over is two-thirds tailings, which is dumped onto piles bearing such names as “Kilimanjaro.” Only the first third is valuable — it is processed into a variety of products, primarily fertilizer (see box). On our return trip underground we pass workshops where, among other things, the meter-high tires are put onto the wheeled loaders, before we finally reach the main station of the mine rescue team. Wendrich and his colleagues demon- strate one of the self-designed emergen-cy vehicles. “You can’t buy something like this,” he says as he pulls draw-ers out of the flat superstructure and

Underground control rooms are not much different from those above ground, but much of the firefighting equipment is made in-house or specially commissioned. For example, the fire truck on the left has a low body so that it won’t scrape against the roof.

Good planning, inspections, preparations, and practice runs ensure quick assistance in emergencies underground. And that can be critical given that unpleasant surprises are commonplace enough at a depth of 1,000 meters.

shows the turret on which the extended- duration respiratory protective devices are stacked.

expertise and camaraderie

Down here you get a really good impres-sion of the team members’ camaraderie and expertise. “Everyone here has had a year of probation before he’s accepted into the mine rescue team,” says Wen-drich, who considers not only the appli-cants’ qualifications as electricians or welders, for example, but also their abili-ty to handle physical strain and get along with the team. People must be complete-ly dependable underground, and “every-thing has to be planned in such a way that it’s three times as safe as necessary,” says Wendrich. Applicants who have already worked in a rescue team above ground are more likely to be accepted, although even

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“If you want to provide effective help in an emergency underground, it’s espe-cially important that you conduct fre-quent practice runs and plan everything in detail,” says Wendrich. “Every maneu-ver must always be made with the utmost precision.” As a result, the team mem-bers receive far more medical training, for example, than do their counterparts above ground. “For instance, we can pre-pare everything for an infusion in advance so that a doctor can immediately begin to work when he arrives.” The team mem-bers’ faith in one another knows almost no bounds. “Of course whenever one of us has had a very stressful assignment, we always talk about it,” says Wendrich. Anyone who has experienced Wendrich and his team in action knows that he’ll be in good hands if an accident should ever occur underground. Nils Schiffhauer

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Background explosion protection


Hot Pellets Trigger gas alarmthe first part of our series of articles on “Detection of Flammable liquids” (see Dräger review 98, pp. 20 ff.) discussed the physical and safety-relevant properties of flammable vapors. part 2 covers their deTecTion. two different measurement methods have proven effective here: the thermocatalytic method and the infrared-optical method. the latter will be covered in the next issue.

How does a sensor reliably detect flammable gases? In principle by the fact that they burn flamelessly and oxidize at a heated catalyst, such as the catalytic converter in the exhaust system of an automobile. Here, for example, tox-ic CO and uncombusted hydrocarbons are oxidized to form “less harmful” CO2.

The fact that the catalyst becomes slightly hotter is just a side-effect of this process. The thermocatalytic method utilizes this side-effect, however. In fact, this “heat effect of a reaction” is the basis of mea-surement using what the gas detection industry typically refers to as a “catalytic bead sensor.” But what actually goes on inside this seemingly simple sensor?

The catalytic effect

The aggressiveness of the oxygen is ulti-mately responsible for the heat effect measurement principle. Oxygen mole-cules love metallic surfaces. They cling tightly to them, split apart (one oxygen molecule becomes two oxygen atoms), and briefly assume a highly reactive state. The oxygen atoms are now just sit-ting there with unoccupied bonds, wait-ing for a reaction partner. And if the oxy-gen doesn’t react directly with the metal, it does so indirectly by first undergoing a prior reaction with moisture — the pro-cess we commonly refer to as “rusting” (oxidation).

Even the surfaces of very noble met-als such as platinum or palladium take on a coating of oxygen. Considered on the microscopic scale, this coating is an equilibrium state. After all, the oxygen atom is quite impatient. If it doesn’t find Just two tiny pellets inside the sensor protect an entire area containing a potentially explosive atmosphere.

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Hot Pellets Trigger Gas AlarmThe first part of our series of articles on “Detection of Flammable Liquids” (see Dräger review 98, pp. 20 ff.) discussed the physical and safety-relevant properties of flammable vapors. Part 2 covers their deTecTion. Two different measurement methods have proven effective here: the thermocatalytic method and the infrared-optical method. The latter will be covered in the next issue.

How does A sensor reliably detect flammable gases? In principle by the fact that they burn flamelessly and oxidize at a heated catalyst, such as the catalytic converter in the exhaust system of an automobile. Here, for example, tox-ic CO and uncombusted hydrocarbons are oxidized to form “less harmful” CO2.

The fact that the catalyst becomes slightly hotter is just a side-effect of this process. The thermocatalytic method utilizes this side-effect, however. In fact, this “heat effect of a reaction” is the basis of mea-surement using what the gas detection industry typically refers to as a “catalytic bead sensor.” But what actually goes on inside this seemingly simple sensor?

The catalytic effect

The aggressiveness of the oxygen is ulti-mately responsible for the heat effect measurement principle. Oxygen mole-cules love metallic surfaces. They cling tightly to them, split apart (one oxygen molecule becomes two oxygen atoms), and briefly assume a highly reactive state. The oxygen atoms are now just sit-ting there with unoccupied bonds, wait-ing for a reaction partner. And if the oxy-gen doesn’t react directly with the metal, it does so indirectly by first undergoing a prior reaction with moisture — the pro-cess we commonly refer to as “rusting” (oxidation).

Even the surfaces of very noble met-als such as platinum or palladium take on a coating of oxygen. Considered on the microscopic scale, this coating is an equilibrium state. After all, the oxygen atom is quite impatient. If it doesn’t find

an appropriate reaction partner relative-ly quickly (palladium is too noble for it), it pairs up with another oxygen atom. In other words, it “recombines” and flies off, making room for other oxygen mol-ecules, which move in to take its place. If an oxidizable molecule of a flamma-ble, gaseous substance comes along, the oxygen strikes: The molecule is quick-ly converted to CO2 and H2O. However, this is only the case if the oxygen atoms are more strongly attracted to this mole-cule than they are to their metallic sub-strate. This force of attraction can be controlled. The hotter the surface, the easier it is for the oxygen atoms to sepa-rate from it again. And if it is too hot, they won’t even dock on the surface at all! A hot metallic surface is therefore used as a roundabout path to force a reaction that would not normally take place at all. The metal is unchanged by this process;

it acts as a reaction facilitator — a cata-lyst. The location at which this reaction takes place is generically referred to as the catalytic center.

But what happens during a reaction of this type? Heat of reaction is released, heating the catalytic center and its sur-roundings. To make this slight heat-ing measurable, you need as many of these catalytic centers as possible in the smallest possible body. This is necessary, because only small masses can be heat-ed perceptibly with such slight amounts of energy. A highly porous body similar to the completely air-permeable materi-al of a flower pot would be ideal, as fired clay or ceramic has countless micropores and channels. As a result, it makes good sense to take a small ceramic pellet and impregnate it during the production pro-cess with catalytic material! A pellet of this type measuring only one millimeter

what signal is produced by 10 % LeL octane?The resistance of a platinum wire as a function of its temperature T (in °C) can be calculated according to eN 60751. The resistance r0 required to do so is approximately 0.928 times the resistance measured at 20 °C. This cold resistance r20 can be measured directly with a resistance thermometer when the catalytic bead sensor is turned off. at 20 °C it is 1.6 ohms. in other words, r0 = 1.48 ohms.

The hot resistance r is measured during operation: at a filament current of 270 ma, the voltage is 1,200 mv, i.e., r = 1,200/270 = 4.440 ohms. The temperature can be calculated using the formula given in eN 60571 and is 558 °C. upon exposure to 10 % LeL octane (= 800 ppm), the voltage increases from 1,200 mv to 1,204 mv, and the hot resistance increases to 1,204/270 = 4.459 ohms. The increase in resistance is only 0.019 ohm! using the cited formula, one can then compute that the tempera-ture of the platinum coil increases to 562 °C. The temperature increases by only 4 °C when exposed to 10 % LeL octane.Just two tiny pellets inside the sensor protect an entire area containing a potentially explosive atmosphere.

explosion-proof design: The gas enters the robust stainless steel housing through a sinter disk (left). The platinum spiral (right) is a coil barely 1 mm wide with a wire diameter of only around 0.05 mm.

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in diameter has an enormous catalytical-ly active surface area (> 0,1 m2), and its countless pores are flooded with air, i.e., all of the catalytic centers are saturated with highly reactive oxygen.

The finely distributed metallic cata-lyst gives the pellet its grey-black color. A small platinum spiral heating element is embedded in the pellet to optimize its temperature. An electrical current of around 270 mA is sufficient to heat the pellet to over 500 °C. Should any flam-mable gases enter the pores, they will further heat the catalytic centers and thus heat the pellet. The platinum heat-ing element becomes hotter in turn, and its electrical resistance increases slight-ly. Ultimately, the whole process comes down to a resistance measurement in the milli ohm range that makes the gas concentration measurable. As long as the heating current through the platinum remains constant, a voltage measure-ment in the millivolt range is enough to

achieve this (see box). The combination of pellet and resistor gives the sensor type its technical name: a pellistor.

Explosion protection

The temperature of such a pellistor only increases by a few degrees when a flam-mable gas is present. Variations in the ambient temperature can be much great-er, and must therefore be compensated for. This can be accomplished using a completely identically structured pelli-stor — a “compensator,” which, howev-er, does not contain any catalyst, and so appears white and is insensitive to gas. The difference signal between the two is the only quantity that is measured. If the temperature of both pellistors chang-es, the measurement signal remains unchanged. This setup works well. How-ever a black pellistor radiates heat away more strongly than a white one, and that in turn leads to an asymmetry between the resistances and a loss of measure-

ment quality. The results are significantly better when two black pellistors are used, and a net effect is achieved by encapsu-lating one of the pellistors so that it only has access to the outside world via a pin-hole. Only the unencapsulated pellistor serves as a measuring element for gas-es, the encapsulated one serves as the compensator.

There are a large number of flam-mable gases and vapors which could be ignited, should their concentration exceed 100 percent of their lower explo-sive limit (LEL) when they came into contact with a pair of pellistors at 400–500 °C. To prevent a catalytic bead sen-sor becoming a source of ignition, it is necessary to ensure that the sensor hous-ing can resist any ignition that occurs within it, and that any flame cannot flash back to the outside world.

The internal volume of the sen-sor — which is scarcely the size of a thim-ble — must therefore be encapsulated so that it is pressure-proof and so that gas can only enter via a flame barrier. Such flame barriers — in the form of a metal sinter disk, for example, or a wire mesh — are on the one hand, both fully gas-permeable and, on the other, extin-guish any possible flame thanks to their extremely good thermal conductivity. It is this property that cools the flame tem-perature to below the ignition tempera-ture of the air-gas mixture.

From the point of view of the mea-surement process, it is just as important that such a flame barrier also functions as a barrier to diffusion. This is because the individual molecules must first pass

through the calm air enclosed in the flame barrier. This means that their speed of diffusion limits how quickly they can affect the pellistor. A methane molecule could cover some hundreds of meters in a second. However, it doesn’t manage this feat because it is hemmed in by billions of air molecules, which constantly force it to change speed and direction.

Diffusion is a slow process that evens out concentrations. It occurs essentially because the molecules constantly tend to move to where there are not so many of their own kind. And when they are con-sumed in the pellistor, there is always a zone of low concentration there, which attracts further molecules. The result is a kind of “molecular suction,” which eliminates the need for a pump with such diffusion sensors.

A matter of calibration

A complete catalytic bead sensor is basi-cally just a very precise apparatus for measuring resistance. It’s the calibration that establishes the relationship between gas concentration and measuring sig-nal. If, for example, a sensor is exposed to a concentration of 0.85 volume per-cent of propane — which corresponds to

Catalyst poisonsThe measurement sensitivity of a catalytic bead sensor can change. in addition to aging effects (e.g. desintering of the ceramic pellet, which leads to reduced porosity and fewer catalytic centers) and contamination of the flame barrier (reduced permeability, which in turn leads to lower diffusion speeds), some volatile substances can also render the catalyst unusable. Lead and sulfur compounds are not only poisonous to automotive catalytic converters (which is why these materials are no longer present in fuels), but also have a similar affect on catalytic bead sensors. in general, it is the volatile organic metal compounds such as silicone which block the catalyst for oxygen, while corrosive gases attack it directly and make it unusable. Many “harmless” cooling agents are also considered corrosive, because they release aggressive chlorine or fluorine compounds when burned.

Catalytic bead sensors reliably warn of the risk of explosion

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explosion protection Background

ment quality. The results are significantly better when two black pellistors are used, and a net effect is achieved by encapsu-lating one of the pellistors so that it only has access to the outside world via a pin-hole. Only the unencapsulated pellistor serves as a measuring element for gas-es, the encapsulated one serves as the compensator.

There are a large number of flam-mable gases and vapors which could be ignited, should their concentration exceed 100 percent of their lower explo-sive limit (LEL) when they came into contact with a pair of pellistors at 400–500 °C. To prevent a catalytic bead sen-sor becoming a source of ignition, it is necessary to ensure that the sensor hous-ing can resist any ignition that occurs within it, and that any flame cannot flash back to the outside world.

The internal volume of the sen-sor — which is scarcely the size of a thim-ble — must therefore be encapsulated so that it is pressure-proof and so that gas can only enter via a flame barrier. Such flame barriers — in the form of a metal sinter disk, for example, or a wire mesh — are on the one hand, both fully gas-permeable and, on the other, extin-guish any possible flame thanks to their extremely good thermal conductivity. It is this property that cools the flame tem-perature to below the ignition tempera-ture of the air-gas mixture.

From the point of view of the mea-surement process, it is just as important that such a flame barrier also functions as a barrier to diffusion. This is because the individual molecules must first pass

through the calm air enclosed in the flame barrier. This means that their speed of diffusion limits how quickly they can affect the pellistor. A methane molecule could cover some hundreds of meters in a second. However, it doesn’t manage this feat because it is hemmed in by billions of air molecules, which constantly force it to change speed and direction.

Diffusion is a slow process that evens out concentrations. It occurs essentially because the molecules constantly tend to move to where there are not so many of their own kind. And when they are con-sumed in the pellistor, there is always a zone of low concentration there, which attracts further molecules. The result is a kind of “molecular suction,” which eliminates the need for a pump with such diffusion sensors.

a matter of calibration

A complete catalytic bead sensor is basi-cally just a very precise apparatus for measuring resistance. It’s the calibration that establishes the relationship between gas concentration and measuring sig-nal. If, for example, a sensor is exposed to a concentration of 0.85 volume per-cent of propane — which corresponds to

a concentration of 50 % LEL — the down-stream evaluation electronics must be set in such a way that 50 % LEL is also displayed. If a measurement system cali-brated for propane is exposed to different gases and vapors, however, it will show differing measurement sensitivity. A mea-surement system calibrated for propane will already show full scale deflection when exposed to methane at 50 % of the LEL, while exposure to 50 % LEL toluene vapor will only produce a reading of 30 % LEL. This is important when it comes to safety. In order to obtain a reliable warn-ing, the sensor must always be calibrat-ed in accordance with the substance to which it reacts with the least sensitivity. Only then will the unit give a warning that is too early, rather than too late!

The differing measurement sensitiv-ity is, incidentally, correlated with the molecular size: the larger the molecule, the smaller the measurement signal. The flash point of every flammable liquid is also correlated with the molecular size: the higher the flash point, the lower the measurement signal. Extremely large molecules can no longer be measured using the catalytic bead sensor. However, the temperature of the flash point of such liquids is also well above normal

temperatures. Correspondingly, there is no danger of ignition (see Part 1).

reliable and economical

Correctly calibrated and properly operated, the catalytic bead sensor is a very reliable and economical measuring instrument. It is capable of warning of an explosion hazard even at very high temperatures (up to 150 °C) — a region in which other (electronic) measuring instruments can no longer be used. However, the device requires oxygen. In other words, it does not work in inert atmospheres. But then again there is no risk of an explosion in such atmospheres! On the down side, the presence of catalyst poisons can increase the maintenance effort substantially. The catalytic bead sensor must undergo more frequent function testing if such substanc-es are present. Infrared-optical sensors are not subject to poisoning and also require no oxygen. And even though they cannot detect gases such as hydrogen, carbon monoxide, acetylene, or ammonia, infra-red sensors today have established a repu-tation for themselves not only in safety technology applications, but also in process-related applications worldwide. But more about that in Part 3 in the next issue. dr. Wolfgang Jessel

Methane

Ethene

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Propane

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Propane

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a measurement system calibrated for propane exposed to 50 % LEL toluene will indicate only 30 % LEL.

after calibration for toluene, the reading for toluene is correct, but 50 % LEL n-nonane is only displayed as roughly 34 % LEL.

no compromises: only after calibration for n-nonane are the measurements for the five substances no longer lower than they should be.

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Precision Down to the Last Micrometerventilators can make the difference between life and death, as patients’ lives depend on technology that must function reliably and perfectly. Such technology is produced by Dräger in Lübeck, where Michael Stäbler manages the ventilator Production unit like a highLy eFFicient Precision workshoP.

stäbLer greets his guests with a handshake whose grip feels like a vise. A qualified precision mechanic, Stäbler oversees production of not only ventila-tors but also critical components for oth-er devices. “For these, we serve as the supplier to all Dräger production loca-tions,” he says.

One ventilator in the room bears the label “Made in Germany.” When asked if manufacturing in Germany still makes business sense, Stäbler takes a key com-ponent produced in Lübeck out of a box. “This part consists of a drive unit and a valve that we could never procure any-where else on the global market with this level of quality,” he explains. The central component of a ventilator, the drive unit that Stäbler is showing us, precisely reg-ulates the valve, which itself consists of a small ruby sphere that perfectly seals a double-clamped sapphire ring. To this end, the two-valve components are ground specifically to fit each other, which is why they can only be used as a pair.

Air flows at the speed of sound

When the drive unit lifts the sphere, which is held by a catching box over a plunger, air or oxygen can flow in precise dosag-es through the gap thus created. “Flow” is perhaps not the right term here, since the gas is subjected to 5 bar of pressure. “When it shoots out, it reaches a speed approaching that of sound,” says Stäbler with the serenity of a man whose technol-ogy can control such forces of nature even in the tiniest spaces.

The drive unit uses high-frequency sig-nals to lift the sphere in the valve by only

Dräger produces life-saving equipment — such as this valve — in-house.

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25Dräger review 99 | February 2010

ventilator proDuction InsIght

Precision Down to the Last Micrometerventilators can make the difference between life and death, as patients’ lives depend on technology that must function reliably and perfectly. Such technology is produced by Dräger in lübeck, where Michael Stäbler manages the ventilator production unit like a hIghLy effIcIent PrecIsIon workshoP.

stäbLer greets his guests with a handshake whose grip feels like a vise. A qualified precision mechanic, Stäbler oversees production of not only ventila-tors but also critical components for oth-er devices. “For these, we serve as the supplier to all Dräger production loca-tions,” he says.

One ventilator in the room bears the label “Made in Germany.” When asked if manufacturing in Germany still makes business sense, Stäbler takes a key com-ponent produced in Lübeck out of a box. “This part consists of a drive unit and a valve that we could never procure any-where else on the global market with this level of quality,” he explains. The central component of a ventilator, the drive unit that Stäbler is showing us, precisely reg-ulates the valve, which itself consists of a small ruby sphere that perfectly seals a double-clamped sapphire ring. To this end, the two-valve components are ground specifically to fit each other, which is why they can only be used as a pair.

Air flows at the speed of sound

When the drive unit lifts the sphere, which is held by a catching box over a plunger, air or oxygen can flow in precise dosag-es through the gap thus created. “Flow” is perhaps not the right term here, since the gas is subjected to 5 bar of pressure. “When it shoots out, it reaches a speed approaching that of sound,” says Stäbler with the serenity of a man whose technol-ogy can control such forces of nature even in the tiniest spaces.

The drive unit uses high-frequency sig-nals to lift the sphere in the valve by only

one millimeter, and it does this through-out the entire service life of the ventilator, which can operate for ten to 15 years. This drive unit is made of an annular gap mag-net in whose circular-shaped gap a coil can move back and forth ever so slight-ly in a manner similar to what happens in a loudspeaker when electricity flows through a coil wire and then causes a membrane to oscillate with the help of a magnet. The drive unit, like a loudspeak-er, is thus an electromagnetic converter.

Its design is almost like that of the Holy Grail, as the unit not only has to safely and precisely move the plunger extreme-ly often but also constantly provide the system software with data on the exact location of the plunger at every point in its stroke, which measures only one mil-limeter. “We work here with a precision measured in micrometers,” says Stäbler, pointing to a winding machine used to produce the coils for the displacement sensor of the parallel mixer.

The coil for the valve drive is made at another workstation that houses two rolls of copper wire in two thicknesses, which

are as fine as human hair. The thicker wire is used for the working coil, and the thinner one is wound in the spiral groove formed by the winding of the thicker wire.

Both coils are wound around an alu-minum core and fixed with an adhesive that is also used for automobile brake disks. “Things get hot here, as they do where the brake disks operate — and like the technology used for brakes, this tech-nology is also a matter of life and death,” Stäbler explains as he places the compo-nent, which looked like a simple technical device when he took it out but now seems like a technical marvel, back into the box from which it came.

flexible production through buffered stockpiling

Stäbler then explains how he and his team not only produce ventilators in double-digit numbers week after week for diverse mar-kets under these demanding conditions with regard to precision and quality. He also tells us that they can now significant-ly increase their output with absolutely no loss to quality. So what’s the secret? “Out-put numbers and fast delivery are the fac-tors that determine who gets the order,” Stäbler says. That’s why he not only put together an efficient core team of work-ers but also took steps to ensure that this team could be expanded in a flexible man-ner. That’s what makes his unit a precision workshop where it’s not just about process-es but also the workers’ qualifications and sense of responsibility.

This system is based on strict adher-ence to a structured timetable for produc-tion. “Basically, we differentiate between

never out of breath: Michael stäbler.

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two types of manufacturing: customer-anonymous production, which extends to the modular level, and subsequent cus-tomer-specific production, where the modules are combined with the devices that display the attributes ordered by the customer.” Each Savina ventilator consists of several hundred individual parts com-bined into several main components that are “built to store” as buffers to ensure continuous production even when unit output requirements change. Deter-mining the appropriate stockpiling level always involves balancing costs and deliv-ery speed. “Our internal forecasts are gen-erally very good here,” Stäbler says.

Information is the key

Each module is built in Lübeck by expe-rienced specialists, partly on one of the so-called clean workbenches, where a fil-tering system reduces to 100 the usual amount of 350,000–450,000 dust parti-cles (measuring more than 0.5 microm-eters) per cubic foot (approx. 28.3 liters). The “normal” workstations, on the other hand, are arranged in a square around the central assembly area. These work-stations are designed as flexible tables to which materials are sent from behind. “This enables us to quickly rearrange the workstations depending on require-ments. We also have supply lines that can be lowered from a suspended ceil-ing, which makes us even more flexible,” Stäbler explains. This concept also opti-mizes each individual process step.

Speaking of optimization, there is also a continual review process at each production point to determine how the

targets for product reliability and quality can be reached even more efficiently. “We don’t have any burning desire to produce any components here that we can procure at the same quality on the market,” says Stäbler, who considers himself in com-petition with external suppliers when it comes to providing other Dräger produc-tion locations with components. Never-theless, there’s no getting around the fact that critical parts, such as the electrome-chanical components, must be manu-factured in Lübeck. Even so, efficiency potential can constantly be exploited at the Lübeck unit. Stäbler recalls a com-plete cleanroom that was only needed for the production of just 20 percent of all components: “That’s why we introduced the ‘clean workbenches,’ which speed-ed up production and made things less stressful for our employees.”

The workforce does in fact form the core of Dräger’s high-quality pro-duction — along with the technology, of course. Stäbler relies here on a collegial concept that involves experts who look beyond their specialized areas. “Informa-tion is the key — everyone needs to know what share of the final product is account-ed for by his or her work,” he says. Such a concept requires that the employees take on responsibility. Final assembly work-ers therefore often decide for themselves whether they want to build the product completely on their own or divide the indi-vidual steps among themselves. “Long-standing employees naturally tend to want to do the complete assembly them-selves,” says Stäbler, who adds that such an approach can not be employed with the

teamwork: An optimal workstation layout safeguards quality.

high concentration: the wristband conducts static charges away from the workpiece (left). the ventilation devices undergo long-term tests (right).

“turnkey” here means that when customers remove the packaging completely, they have assembled, tailor-made ventilators.

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targets for product reliability and quality can be reached even more efficiently. “We don’t have any burning desire to produce any components here that we can procure at the same quality on the market,” says Stäbler, who considers himself in com-petition with external suppliers when it comes to providing other Dräger produc-tion locations with components. Never-theless, there’s no getting around the fact that critical parts, such as the electrome-chanical components, must be manu-factured in Lübeck. Even so, efficiency potential can constantly be exploited at the Lübeck unit. Stäbler recalls a com-plete cleanroom that was only needed for the production of just 20 percent of all components: “That’s why we introduced the ‘clean workbenches,’ which speed-ed up production and made things less stressful for our employees.”

The workforce does in fact form the core of Dräger’s high-quality pro-duction — along with the technology, of course. Stäbler relies here on a collegial concept that involves experts who look beyond their specialized areas. “Informa-tion is the key — everyone needs to know what share of the final product is account-ed for by his or her work,” he says. Such a concept requires that the employees take on responsibility. Final assembly work-ers therefore often decide for themselves whether they want to build the product completely on their own or divide the indi-vidual steps among themselves. “Long-standing employees naturally tend to want to do the complete assembly them-selves,” says Stäbler, who adds that such an approach can not be employed with the

newly trained employees who are used to address peaks in demand.

The finished devices are put through stringent and complex internal testing procedures that begin with high-voltage stability checks at 1,500 volts. After that, each unit is operated at full load for 12 hours in a hot room with a temperature of 40 °C. “Ventilators like the Savina in par-ticular are often used in countries where such temperatures are common,” Stäbler explains. The latter test is followed by a check of all mechanical, electrical, safety, operational, and command functions that lasts for at least 75 minutes. “We use qual-ified experts for these,” says Stäbler, add-ing that such specialists must have perfect knowledge of the testing stipulations for obtaining approval in various countries around the world.

Key moments

Savinas are delivered with the exact con-figurations specified in their orders. It’s literally a turnkey delivery. To prove the point, Stäbler reaches for a hex key that comes with every device: “It’s always a ‘key moment’ for us when we see how happy customers are to get this little tool. For them, it’s not just a hexagon-shaped piece of steel. Instead, it also shows them that we thought about customer utility at every stage of the production process.” Customers simply open the device’s out-er packaging, after which the Savina can more or less immediately be rolled to wherever it’s needed.

Back in his office, Stäbler turns to the issues of quality, creativity, and lead-ership: “Basically, anyone can do any-

thing they put their mind to,” he says. The important thing is to carefully examine the potential obstacles that might prevent them from doing so — and then eliminate them. This in turn requires creativity, or “thinking outside the box.” That’s also the title of a book Stäbler now mentions. The book’s cover shows how one can link nine points arranged in a square using only four lines by thinking “outside the box.” Another important ingredient for success is team spirit — not just in production but also as an element of cooperation with other company units and departments. Stäbler also likes to show international customers touring the production lines in Lübeck how quality and reliability are produced at the facility.

If one were looking for a single word to describe the concept behind this high-tech, precision workshop production oper-ation, one might come up with the term “flow.” This term would apply not only to things like the highly precisely channeled flow of air through the ruby sphere and the sapphire ring inside the ventilator, but also to the “flow” that was described by American psychologist Mihaly Csikszent-mihalyi to explain a form of work organi-zation that is highly desirable. Such a sys-tem is characterized by employees who “lose themselves” in tasks that are aimed at meaningful objectives and require the workers to exercise independent think-ing and a sense of responsibility. From the very first handshake, it was clear that Stäbler subscribes to this philosophy. And now it’s equally evident that he has sys-tematically implemented it in his unit’s daily work. Nils Schiffhauer

In the end, turnkey delivery shows that customer utility is considered from the very beginning

Teamwork: An optimal workstation layout safeguards quality.

High concentration: The wristband conducts static charges away from the workpiece (left). The ventilation devices undergo long-term tests (right).

“Turnkey” here means that when customers remove the packaging completely, they have assembled, tailor-made ventilators.

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OutlOOk Fire Departments

Research for the FutureFiRe pROtectiOn will have to change in germany in the coming years in response to demographic shifts and new types of assignments. Current research projects are already paving the way for tomorrow’s firefighting technology and organizational structures.

in the FutuRe, the personal pro-tective equipment (PPE) of Germany’s firefighters will include telemetric and personal localization technology, as well as virtual reality systems and nanomate-rials. These innovative technologies are responses to the changes fire departments will face in the first 25 years of the 21st century. The number of firefighters will decline over the medium term, while assignments such as emergency help and disaster relief after natural catastro-phes will tend to increase, according to Silvia Darmstädter, spokesperson of the German Fire Department Association (DFV). “However, fire departments will have to remain an integral part of the array of services provided by municipal-ities,” she says.

Germany is “very aware of the dif-ficulties faced by fire departments as a result of demographic and other chang-es,” emphasizes Berthold Penkert, Depu-ty Director of the Fire Department Insti-tute in North Rhine-Westphalia. The fire departments, with their more than one million active members and around 250,000 junior firefighters, are therefore taking a proactive approach to shaping this change. For example, the German Fire Protection Association (GFPA) held a “future workshop” as early as 2002, in which it stated that the key require-ments included improvements in com-munication technology and the promo-tion of basic research. The DFV program titled “DFV 2020 — Strategies for a Safe Future,” which was drawn up in 2008, calls, among other things, for improved training and the stronger promotion of

young people. In 2008 the DFV also orga-nized a future congress, during which a panel discussed the technologies and organizational structures that would be viable in the future. One of the panel’s appeals was for the introduction of stan-dardized PPE throughout Germany. This equipment could then be customized for special needs, depending on the firefight-er’s assignments and tasks.

nanocoatings for protection

How these visions could be technically implemented in reality is described by Dr. Sabine Richter, a researcher at the Fire Department Institute in Saxony-An-halt. Among the areas being researched by scientists are new materials for fire-fighting equipment, she says. Examples include nanocoatings for improved pro-tection against heat, moisture, and haz-ardous substances, and coatings that show if certain limits are exceeded, such as overheating during use in a fire.

However, the biggest boost in inno-vation will affect PPE as a whole. “The incorporation of ‘wearables’ into pro-tective clothing will further improve its effectiveness,” forecasts Dr. Richter. Examples include systems for the telem-etric transmission of vital signs, making it possible for the operation controllers to monitor the firefighters’ heartbeat, respi-ratory rate, and core body temperature. The PPE also needs to continuously mea-sure the temperature and the concentra-tion of hazardous substances.

Such a concept is currently being worked on by the Department of Tex-tile and Clothing Technology of Nieder-

rhein University of Applied Sciences in Mönchengladbach. In this system, sen-sors underneath the PPE continuously measure the firefighters’ vital signs. “If values reach critical levels, the incident commander can notify the firefighters to save themselves in time,” explains Dr. Andrea Tillmanns.

The firefighter helmets of tomorrow could become information and commu-nication centers for their wearers via a voice transmission system and a head-mounted display (HMD) for showing information. This kind of customized protection and measuring equipment is being made possible through the minia-turization of systems, the combination of various functions in a single device, and new data transmission technologies.

The German Ministry of Education and Research (BMBF) is promoting PPE particularly through the Sensprocloth project of the research area Integrated Protection Systems for Security and Emer-gency Services. The aim of this project is to develop an integrated sensory clothing sys-tem for fire brigades and disaster manage-ment. In addition to devices for measuring vital signs and surrounding conditions, the clothing will integrate a communication system and technology for the localization of firefighters during operations.

Communication and localization are also key features of the Safe research proj-ect for semipermeable protective cloth-ing, which is also being supported by the ministry. The aim of the project is to enhance the firefighting teams’ safety and comfort so that they can be deployed for longer periods. The Lumitext project, on > S

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Forschung Ausblick

Although risks will certainly remain,

research will help improve safety

even further.

Research for the FutureFiRe pRotection will have to change in germany in the coming years in response to demographic shifts and new types of assignments. current research projects are already paving the way for tomorrow’s firefighting technology and organizational structures.

rhein University of Applied Sciences in Mönchengladbach. In this system, sen-sors underneath the PPE continuously measure the firefighters’ vital signs. “If values reach critical levels, the incident commander can notify the firefighters to save themselves in time,” explains Dr. Andrea Tillmanns.

The firefighter helmets of tomorrow could become information and commu-nication centers for their wearers via a voice transmission system and a head-mounted display (HMD) for showing information. This kind of customized protection and measuring equipment is being made possible through the minia-turization of systems, the combination of various functions in a single device, and new data transmission technologies.

The German Ministry of Education and Research (BMBF) is promoting PPE particularly through the Sensprocloth project of the research area Integrated Protection Systems for Security and Emer-gency Services. The aim of this project is to develop an integrated sensory clothing sys-tem for fire brigades and disaster manage-ment. In addition to devices for measuring vital signs and surrounding conditions, the clothing will integrate a communication system and technology for the localization of firefighters during operations.

Communication and localization are also key features of the Safe research proj-ect for semipermeable protective cloth-ing, which is also being supported by the ministry. The aim of the project is to enhance the firefighting teams’ safety and comfort so that they can be deployed for longer periods. The Lumitext project, on > S

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OUTLOOK Fire Departments

the other hand, aims to create new kinds of firefighting gear with a warning func-tion, i.e. textiles with electroluminescent properties for protective clothing and technical applications. Unlike conven-tional passive reflectors, the new lumi-nescent effects could be specifically acti-vated in the future.

Another project, known as Landmarke, aims to provide firefighters with interac-tive navigation. While in action, firefight-ers would distribute probes equipped with sensor and transmission technology. In combination with interactive PPE, such markings would make it easier to navigate even under the most difficult conditions.

However, improving firefighters’ bun-ker gear is just one of several factors that need to be addressed when it comes to the future of fire protection in Germa-ny. Of crucial importance for safeguard-ing the current system is stronger sup-port for training young people, accepting a larger share of applicants from youth bri-gades, and updating training programs. The future of firefighting in Germany will also entail changes to communica-tion and organizational structures, as has

been frequently pointed out by the GFPA, the DFV, and others. In addition to sup-porting research, the BMBF also considers “organization and the intelligent struc-turing of operations” to be a challenge. That’s because during most future oper-ations several fire departments will have to cooperate, meeting at the scene of the fire. Local fire departments will be sup-ported by external specialists.

Use of helicopters in the future?

The idea of using helicopters to rein-force firefighting teams in thinly popu-lated areas was first discussed in 2006. A year later the proposal was included in a GFPA study on how demographic change would affect fire departments, since heli-copters would ensure that enough fire-fighters with breathing apparatus would also be available during daylight hours on weekdays throughout rural districts. However, state-of-the-art communica-tion equipment is needed for such sce-narios, not only in Germany. In its Emerc research project, Upper Austria Univer-sity of Applied Sciences has developed a digital system to provide firefighters with

an array of information, including dig-ital maps, motor vehicle rescue sheets, and data on hazardous substances. Digi-tal systems will also change the way fire-fighters are trained, affecting everything from the operation of equipment used in training for typical assignments under real-life conditions to the simulation of major fires and disasters. Among the pro-grams currently under way in this area are the EU project Virtual Fires and the simulation portion of the Spider program (Security System for Public Institutions in Disastrous Emergency Scenarios), which is also funded by the BMBF.

The development of fire departments is a very dynamic process in which inno-vative technical solutions play a key role. In the final report on its future workshop, the GFPA states that everyone will benefit from investment in research and innova-tion of fire protection and disaster man-agement in Germany. Fire departments and citizens will benefit from the latest safety standards, and research institutes and industrial companies can stay ahead of their international competitors in the area of safety technology. Peter Thomas

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The Leibniz Institute for New Materials in Saarbrücken, Germany, is also conducting research to improve safety in the future (left). The picture on the right shows a developed fabric, which has a nanoparticle surface that causes liquids to simply roll off.

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31

Service


reSpiratory protection and portable gaS detection equipment SaleS by location

nortH Albert-Schweitzer-Ring 22 22045 Hamburg Tel. +49 40 668 67 0 Fax +49 40 668 67 150

eaSt An der Harth 10 b 04416 Markkleeberg Tel. +49 341 35 0 31 173 Fax +49 341 35 0 31 172

SoutH Vor dem Lauch 9 70567 Stuttgart Tel. +49 711 721 99 0 Fax +49 711 721 99 50

WeSt Kimplerstraße 284 47807 Krefeld Tel. +49 2151 37 35 0 Fax +49 2151 37 35 50

SubSidiarieS: auStria Dräger Safety Austria Ges.m.b.H Wallackgasse 8 1230 Wien Tel. +43 1 609 36 02 Fax +43 1 699 62 42

SWitZerland Dräger Safety Schweiz AG Aegertweg 7 8305 Dietlikon Tel. +41 44 805 82 82 Fax +41 44 805 82 80

regionS

europe nortH / central Dräger Safety AG & Co. KGaA Revalstraße 1 23560 Lübeck, Germany Tel. +49 451 882 0 Fax +49 451 882 2080

europe SoutH Dräger Safety France S.A.S. 3c, Route de la Fédération 67025 Strasbourg Cedex, France Tel. +33 3 88 40 76 76 Fax +33 3 88 40 76 67

nortH america Draeger Safety, Inc. 101 Technology Drive Pittsburgh, PA 15275, USA Tel. +1 412 787 8383 Fax +1 412 787 2207

aSia / paciFic Draeger Safety Asia Pte Ltd 67 Ayer Rajah Crescent # 06-03 Singapore 139950 Tel. +65 68 72 92 88 Fax +65 65 12 19 08

HeadquarterS: dräger Safety ag & co. Kgaa revalstraße 1 23560 lübeck, germany tel. +49 451 882 0 Fax +49 451 882 2080 www.draeger.com

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IMPRINTpublisher: Drägerwerk ag & Co. Kgaa, Corporate Communications editorial address: Moislinger allee 53–55, 23542 Lübeck / [email protected], www.draeger.com editor in chief: björn wölke, Tel.: +49 451 882-2009, Fax: +49 451 882-3197 publishing House: tellus PubLiSHiNg gMbH editorial consultant: Nils Schiffhauer (responsible according to press law) art direction, design, and picture editing: redaktion 4 gmbH translation: TransForm gmbH printing: Dräger + wullenwever print+media iSSn 1869-7291

The articles in Dräger review provide information on products and their possible applications in general. They do not constitute any guarantee that a product has specific properties or of its suitability for any specific purpose. all specialist personnel are required to make use exclusively of the skills they have acquired through their education and training and through practical experience. The views, opinions, and statements expressed by the persons named in the texts as well as by the external authors of the articles do not necessarily correspond to those of Drägerwerk ag & Co. Kgaa. Such views, opinions, and statements are solely the opinions of the respective person. Not all of the products named in this magazine are available worldwide. equipment packages can vary from country to country. we reserve the right to make changes to products. The current information is available from your Dräger representative. © Drägerwerk ag & Co. Kgaa, 2010. all rights reserved. This publication may not be reproduced, stored in a data system, or transmitted in any form or using any method whether electronic or mechanical, by means of photocopying, recording, or any other technique in whole or in part without the prior permission of Drägerwerk ag & Co. Kgaa.

31_Service_S 31 20.01.2010 12:32:45 Uhr

All-Round: X-zone 5000 Measures and Gives 360° AlarmThe Dräger X-zone 5000 typically monitors an area with a radius of about 25 meters for hazardous gases. It can increase its radius by interconnecting with up to 25 additional devices to form a wireless fenceline. The personal gas detection instrument X-am 5/5600 1 , which can detect up to six gases, is laid into the intake 2 and charged via contacts 3 . The central power supply is a rechargeable lead-gel battery 4 that operates for 60 hours (12 Ah) or even a complete work week (24 Ah), even in cold en-vironments. Simply placing the battery in a wireless induction charger 5 recharges it within ten hours. The fact that the detector 1 is positioned on the top of the unit allows gas to diffuse into it from all sides independent of the wind direction. Three locking systems 6 that can be locked with half a turn hold the cover cap 7 in place. When the device is in opera-tion the LED ring 8 blinks green and illuminates a ring around it in seg-

ments. If the device 1 detects a gas, the LED color changes from green to red and an alarm 9 is sounded from two speakers mounted in com-plementary directions. The warning is given with a sound pressure level up to 108 dB @ 1 meter over a frequency spectrum ranging from 1,500 to 2,300 Hertz — similar to the sound pressure level of a jackhammer.

A wireless connection that works even in industrial environments auto -matically connects up to 25 mobile warning devices to an alarm fence-line. As soon as a device detects a gas, it provides a visual warning (red) and emits a loud alarm. All the other devices also sound the alarm sig-nal, and these “daughter alarms” display green/red. A rubberized handle 10 makes the device, which weighs between seven and ten kilograms, convenient to carry. Three solid feet 11 keep it stable and ensure suffi-cient floor clearance — to avoid puddles, for example.

CLOSE-UP GAS DETECTION DEVICE

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A K+S mine rescue team covers an area the size of Munich ... · A K+S mine rescue team covers an area the size of Munich Micrometers Precision in manufacturing ventilators Hot Pellets

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