Dräger Review 111 Second issue, 2015 Resilience The invisible force which prevents us from cracking in extreme situations Uncertainty Risk management reduces wrong decisions p. 20 Direct Hit How ballistics authorities test armored vehicles p. 26 Helpers Antibodies are diligent narcotics agents p. 34 Resilience Technology for Life 2015 Dräger Review 111
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Dräger Review Risk management reduces wrong decisions ...€¦ · Second issue, 2015 Resilience The invisible force which prevents us from cracking in extreme situations Uncertainty
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D
räger Review
111 S
econd issue, 2015 R
esilience
The invisible force which prevents us from cracking in extreme situations
Everyone is confronted with situations at some point in their
lives which can drive them to the limits of human tolerance –
limits which often only become apparent later on. Resilience is about
the ability to cope with and recover from difficulties and find-
ing ways of strengthening it.
14 OUTER PROTECTION
A nice shine can also provide good pro tection: Lufthansa Technik uses several dozen different paints to protect their aircraft from corrosion at an altitude of 10,000 meters. This work is done by hand, because the safety of many people is at stake here too. Meanwhile, the employees also have to protect themselves from the solvents.
26 INNER SECURITY
Armored vehicles are fortresses on wheels and offer their occupants security from dangers ranging from hazard ous gases to a hail of bullets. German ballistics authorities test the vehicle concepts in accordance with strict criteria for different threat categories.
4Men of action in Aalborg and PotsdamA Danish senior physician and a German media designer: both men move people with their work in their own special way.
6Coming through bad timesStress, problems, or other worries: everyone faces a demanding situation at some point. Some people cope with crises better than others. They are born with such abilities, while others can acquire them.
14Shining in the troposphereWhether on the ground or in the sky, aircraft have to withstand quite a lot. This is also why they are en-hanced – with up to 25 coats of paint.
20Fear, anxiety, riskThe greatest fear is that of the unknown. Risk management allows the unexpected to be con-trolled in a rational way – so that fear doesn’t take control.
26B-A-N-G!Ballistics authorities are concerned with neither onomatopoeia nor comics. The resistance of vehicle armor is tested here.
The articles in Dräger Review provide information on pr oducts and t heir possible applications in general. They do not constitute any guarantee t hat a product has specifi c properties or is suitable for any specifi c purpose. Specialist personnel are required to make use exclusively of the skills they have acquired through their educa-
EDITOR-IN-CHIEF: Björn Wölke, Tel. +49-451-882-2009, Fax +49-451-882-7-2009 EDITING CONSULTANT: Nils Schiffhauer ART DIRECTION, DESIGN, IMAGE EDITING, AND COORDINATION:Redaktion 4 GmbHTRANSLATION: Lektornet GmbHPRINT: Lehmann Offsetdruck GmbH ISSN: 1869-7275CODE NUMBER: 90 70 396
www.draeger.com
IMPRINT30Red and white rescuers Hamburg Fire Department responds to around 700 calls a day – as firefighters in red and paramedics in white. A day in the Hanseatic city.
34Sensitive narcotics agents They are the heroes of the saliva test in a manner of speaking – anti bodies that detect drugs selec-tively and highly sensitively.
40Lots of ashFor fire investigators ash and other remains are like a crime story which is sometimes easy and some-times difficult to read.
44Explosive conditions undergroundIt’s not dragons, but toxic gases that miners have to watch out for.
50Sensitive sleuthsSmall yet mighty: electro-chemical sensors measure gases to protect human life.
56Fresh airA silent blower unit draws in ambient air to purify it – find out how it is done.
Lars Kjærsgaard, Senior Physician, Aalborg University Hospital / Denmark
“Not every procedure works the same on every patient. Naturally there are statistics, algorithms, and science. But contact with the patient is essential if you want to find the right intensive care therapy. That is also the reason why I deal with the 60 charge nurses on a level play-ing field. I spend an hour a day
with the patients, but the nurses are with them all day. For example, if I prescribe a respiratory mask, it is generally an unpleasant expe ri-ence – the patients perspire underneath it and some even get claustrophobia. The role of the nurses is to then ensure that the patient understands how important it is to accept the treat-ment. I didn’t learn to establish this trust in all my years at univer-sity. When we needed new re s -
pira tors, the nursing staff helped to choose them. Of course, the technical features were important, but the nurses stressed how im portant it was to them to receive intensive training on how to use the res pirators. Every time I approach a patient’s bed, I greet them – even if they are sedated. Sometimes they take in something. There is nothing more demeaning than a doctor who starts to treat a patient without greeting them first.”
Mario Schuster, Media Designer, Art-EFX, Potsdam / Germany “Yes, my four children know what I do for a living. If we are walking around the city, they regularly ask me if I did that. Often I am able to say ‘Yes, I did that picture.’ I design faça des, substations, and interiors. A worker at a youth club discovered my passion for spraying. I come from Kleinmachnow near Potsdam – I was able to spray legally there. I don’t really have any artistic role mod-els, but the pictures of Gerhard Richter fascinate me. I actually wanted to go to university, but professional s praying was ultimately more fun. In the beginning we worked seven days a week. Now I am the artistic director at Art-EFX and am res-ponsible for Schleswig-Holstein, among other places. Are you familiar with the small town of Süderbrarup? I im-proved the look of the substations there for an energy supplier. When you’re working ten hours a day, you see little of the landscape. I spray freehand using an A4 sheet of paper as a template. And if a customer de-cides that they want to add their purring cat to the finished picture, it’s no problem! I simply put the mask on, reach into the box where the cans are stored, and carry on spraying. Then they are happy – as are my chil-dren when I walk past it with them.”
Work-related stress, private problems, or other worries: everyone finds themselves in a stressful situation at some point in their lives. Resilient people MASTER CRISES MORE EASILY. Some people are born with such abilities, while others acquire them – people, companies, or even entire cities.
Text: Isabell Spilker
The Strength of
Resilient due to the job? Three people died and many others were injured in a multiple pileup on the A31 in North Rhine-Westphalia. Emergency workers shielded the accident from those who perhaps wouldn’t have been able to cope with it – and ultimately needed to muster a lot of strength themselves to come to terms with what had happened
the ResilientDraeger_EN_02-2015_007 7Draeger_EN_02-2015_007 7 26.05.15 13:4426.05.15 13:44
8 DRÄGER REVIEW 111 | 2 / 2015
FOCUS MENTAL STRENGTH
The emergency call was received by the call center at 9:33 a.m. What happened in the hours that followed would re-quire thousands of workers and drive them to the limit of human tolerance. In March 2009 a former student of a school in the small town of Winnenden in Baden-Württemberg shot dead 15 people – and ultimately himself. Martin Luitjens was also on the scene. As a leading emergency pastoral care worker he took care of the survivors and emer-gency crews by being there to talk to them. By the time evening came, the man who usually helps oth-ers to cope with traumatic experiences noticed that even his strength was waning. Emergency crews who have to recover children’s bodies, police officers who witness their colleagues being gunned down – they all work in these inhuman situations. Once everything has calmed down, stress takes its toll. However, those who do not possess the mechanism that psychologists call “resilience” will have big problems coping with
T
their everyday lives. “People who come home after such a day at work are not initially in a position to come to terms with what has happened,” says Luitjens, who also works as a resilience coach. “They are disoriented at first, because the psyche needs time.” Some people pull themselves together within a few days, while others need months, sometimes even years – or an entire lifetime.
Tolerance to disruptionsResilience describes the psychological ability to cope with and recover from difficulties. The concept can be assigned to sys-tems, organizations, infrastructures, materials, and entire socie-ties. Across a number of different disciplines it describes people’s tolerance to disruptions – and the ability to take the measures needed to ensure that the serious situation doesn’t even occur in the first place or at the very least mitigate its impact. This works in a hospital as much as within other complex systems. An exam-ple: in recent years the impact of climate change on cities has been analyzed. The focus of the analysis was on how the cities
els of physical exertion, many people are under enormous pres-sure both at work and at home. If you are unable to keep up, you lose – at least that’s how it seems to many people. General stud-ies of the mental health of employees in medical careers reveal, for instance, that at least 20 percent of doctors suffer from burn-out syndrome. Work-related stress is one of the biggest challeng-es of the present age. Resilience is the flip side of it all and the thing that can protect people – like a callus.
“What doesn’t kill me only makes me stronger”Yet how is this protection mechanism formed? Systems can be made more resilient, but people? Resilience can protect the mind and prevent illness after intensive negative experiences. And just like an immune system it is more pronounced and effective in some people than in others. So why are some people more re-silient than others? Is it genetic, is it acquired during childhood, or does it develop during the transition to adulthood? Or can resilience evolve at any of these stages? The formula could be simple. An essen tially optimistic child is not wrapped in cotton wool by its parents, but is exposed to the oc casional crisis. He or she goes through life as a mentally strong adult and faces any adversity with an inner robust-ness. Stephen Joseph carries out research in precisely this area. He coordinates the psycho-therapeutic and practical psychology course at the School of Education at the Universi-ty of Nottingham and was head of the Cen-tre for Trauma, Resilience and Growth there until 2013 as professor of psychology: “Many of the skills that adults possess are the result of training during childhood. We must learn how to cope with difficult situations. Those who are confronted with adversity and catas-trophe will show a higher degree of resilience
TOUGH SHELL
The American Psychological Association has developed a ten-point plan which can pave the way to greater resilience:
1. Make connections. 2. Avoid seeing crises as insurmountable problems.3. Accept that change is a part of living.4. Move toward your goals. 5. Take decisive actions.6. Look for opportunities for “self-discovery.”7. Nurture a positive view of yourself. 8. Keep things in perspective.9. Maintain a hopeful outlook.10. Take care of yourself.
The noise was alarming, the scene incomprehensible: on June 3, 1998 the high-speed ICE train “Wilhelm Conrad Röntgen” derailed in Eschede near Celle. The train accident was the first major catastrophe in Germany in which the emergency crews received systematic follow-up care. A total of 700 of around 2,000 workers took advantage of the assistance over a period of three years; 100 had long-term problems – they suffered from internal unrest and could barely sleep
Resilience can protect the mind – like an immune system
manage to brave the extreme weather and return to normality as quickly as possible afterward. An aptitude for learning is a fur-ther dimension of this robustness and capacity to cope. A resil-ient system is in a position to learn and adapt to changing condi-tions. “In relation to people, resilience describes the mechanisms which ensure that they emerge stronger from stressful and de-manding situations,” explains Michèle Wessa, professor of clini-cal psychology and neuropsychology at the Johannes Gutenberg University in Mainz. Europe’s first center for resilience research opened here in the summer of 2014 with the aim of understand-ing the principles of resilience on a molecular and neuroscientific level and by conducting animal experiments. The idea is to devel-op new prevention methods on the basis of the findings.
The demand for effective concepts is rising. The psycholog-ical constitution of man has become a popular subject. Despite increased prosperity and (compared to bygone days) lower lev-
if they have learned from early experiences.” Accord-ingly, he also essentially sees the positive side of cri-ses and concurs with Friedrich Nietzsche’s Twilight of the Idols: “What doesn’t kill me only makes me stron-ger.” Stephen Joseph borrowed from Nietzsche for the title of his book (What Doesn’t Kill Us) and tells sto-ries of people who have managed to emerge stron-ger from setbacks. “Post- traumatic growth also means learning from trauma: setting new priorities and find-ing out what is really important.” However, those who have no positive experience of coping with crises, that is to say those who have been unable to come to terms with previous ex-periences, will be more vulnerable. This has also been shown by a study in which Joseph was involved in 1987 following the ferry disaster near the Belgian port of Zeebrugge in which 193 peo-ple died. Survivors who had to deal with further crises (such as a severe illness or the loss of a relative) in the three years after-ward proved to be even more vulnerable than a reference group.
“Those who are as cool as a cucumber are by no means resilient”Something else became clear from the study: people who were unable to show their feelings and who lacked social support fared especially badly. A finding also shared by resilience coach Luitjens: “Social support is a driving factor. Resilience has a great deal to do with the personal environment – as in the case of emergen-cy crews, for instance. The culture within the organization will also determine how resilient they are.” Is it not possible to sim-
ply talk to one another after a callout and just say that some-thing didn’t go so perfectly? “Structures which live by the myth of being invulnerable and in all probability being able to remain as cool as a cucumber make it difficult to deal with demanding situations. In such an environment hardly anyone has the cour-age to admit to a supposed weakness.” In his opinion and expe-rience, social resources – in other words, the support within the group – are the crucial factors which lead to greater resilience. The researcher Michèle Wessa goes one step further here: “The link is not as strong as people thought. Although these attributes and factors (optimism, social support, and early experiences) do have a significant influence, they are not sufficient to predict how resilient an individual will be in a situation.” Resilience is proba-bly a combination of different factors and mechanisms. “If it were merely attributes that made us resilient, then somebody would re-main resilient throughout their entire life. But that isn’t the case. An example: many emergency workers go through their profes-sional lives without suffering any damage – and then something suddenly knocks them off their feet. This seems to confirm that there are resources which are somehow built up over time, but can also be exhausted at some point.
Inherent feature of many training coursesThe German Resilience Center is trying to catch this moment with a specially established outpatient clinic. It is not aimed at people who are in the middle of a crisis and are in desperate need of resilience; it is more for stressed people and institutions be-fore the first serious situation occurs so that it can be countered
“The culture within the organi-zation will also determine how resilient emergency workers are”
Entering the water with the hope of find-ing survivors,
Five years ago Dräger set up a division which tests medical-technical equipment in more practice-based settings, making it more resilient to adverse environmental influences. Dirk Zumtobel is head of the product reliability division.
Mr. Zumtobel, quality assurance is taken for granted these days. What do you do to go further? Zumtobel: The conventional standards applied to functional testing in the area of quality assurance were no longer sufficient for us. We also test system stability over a longer period of time – and under “clinical conditions.” Flawless components do not necessarily produce a perfect system. This is precisely what we work on: we make sure that our components are free from defects and function within the overall system in everyday use.
Have you built a small hospital for this purpose?Zumtobel: Yes, kind of. In our quality lab we are technically in a position to simulate everyday clinical situations. We subject 25 or more devices of a certain type to stress under various conditions, record the results, and evaluate them statistically. This makes it possible to give statements about the robustness and reliability of our systems in the field.What conditions do you subject the equipment to?Zumtobel: As many predictable ones as possible – severely obese patients, premature babies (who need to be gently ventilated), regular disinfection measures (with various detergents and methods), temperature and pressure changes, power supply fluctuation,and many more besides.What were the initial findings?Zumtobel: After the first test runs with prototypes we were surprised at how many events were actually recorded. Not everything is immediately
noticed by the user. It revealed to use the areas where the system architecture is still “shaky” – in a similar way to a PC system which can also occasionally hang during an application.So the equipment is made resilient against itself in the first instance. What kind of external influences must it also be protected from?Zumtobel: The biggest challenge confronting technology is actually the user. Everything is generally OK as long as the equipment is used in accordance with the operating instructions, if there were no “foresee-able misuse.” To this end, we regu-larly let people with clinical and technical knowledge operate our new techno-logies without formal product training. In addition, we subject the equipment to further unpredictable situations: the use of unsuitable accessories, switch-ing it off suddenly, incorrect cleaning, and much more besides. This gives us more insight which helps us to make the equipment even more resilient during the development phase.
accordingly with stress management and relaxation techniques as well as a social network which offers assistance. Measures that promote resilience are often an inherent feature of training courses for firefighters, police officers, and pilots. It is important to realize the following: “There is no such thing as resilient or not resilient! Every individual has a certain limit which is sometimes sufficient for the challenges they face – but sometimes they go beyond this limit,” says Martin Luitjens. It took three days for him to regain his com-posure after his experiences in Winnenden. “Naturally I know about the coping process and what I need to do to get back on my feet.” Luitjens is well equipped. However, he also knows that even though an individ-ual reacted resiliently to a certain situation last year, it doesn’t necessarily mean that they will do so again on the next occasion. Nothing can be predicted, but everyone can arm themselves against it.
“There is no such thing as resilient or not resilient!”
LITERATURE AND LINKS
Stephen Joseph: What Doesn’t Kill Us. 288 pages, Jackson/TN, USA, Basic Books, 2013
Karen Reivich, Andrew Shatte: The Resilience Factor: 7 Keys to Finding Your Inner Strength and Overcoming Life’s Hurdles. 352 pages, Harmony Publishers, New York, 2013
American Psychological Association: www.apa.org/helpcenter/road-resilience.aspx
Resilence Training Institute (Branches throughout the USA)www.resiliencetraininginstitute.com
Even though the job requires a certain robustness, the image of the tough firefighter has changed in recent years. Nowadays, emergency workers can admit that callouts lasting several hours, such as this major fire, can really get to them
HOW STRONG IS YOUR MENTAL IMMUNE SYSTEM?People react very differently to demanding experiences. This is primarily due to their individual mental resilience. Take this test to determine how resilient you are. Mark the box which
generally indicates the extent to which the following state-ments apply to you. Add up all the points at the end – you can check your score below.
1. When I have plans, I see them through.
1 2 3 4 5 6 7
2. I usually manage to do everything somehow.
1 2 3 4 5 6 7
3. I am not thrown off course that easily.
1 2 3 4 5 6 7
4. I like me.
1 2 3 4 5 6 7
5. I can multitask.
1 2 3 4 5 6 7
6. I am decisive.
1 2 3 4 5 6 7
7. I take things as they come.
1 2 3 4 5 6 7
8. I take an interest in many different things.
1 2 3 4 5 6 7
9. I can usually see a situation from more than one perspective.
1 2 3 4 5 6 7
10. I can also force myself to do things that I don’t really want to do.
1 2 3 4 5 6 7
11. When I am in a diffi cult situation, I usually fi nd a way out.
1 2 3 4 5 6 7
12. I have enough energy to do all the things I have to do.
1 2 3 4 5 6 7
13. I can accept the fact that not everybody likes me.
1 2 3 4 5 6 7
Based on: Karena Leppert et al, Klinische Diagnostik und Evaluation magazine, 2008, pp. 226–243; with permission.
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SCORE58 points or less: You are not very resilient. However, this does not mean that you are at the mercy of life’s diffi cult situations, but you are more likely to need help working through a challenging situation than others who are confronted with the same diffi culties.
59 to 82 points: You have average resilience. You can normally deal with diffi cult situations and get back on your feet after a little while.
83 points or more: Nothing throws you off course easily. You have the ability to react fl exibly to adversity and fi nd a strategy appropriate to the situation. If you are unable to change a diffi cult situation, you are generally able to accept it.
AAntonio Borrego looks rather audacious when preparing for
his job. The white disposable suit lacks any kind of fashionable detail; his hands are covered by light blue rubber gloves. The hat with flaps over both ears is reminiscent of the head protec-tion worn by nostalgic motorcyclists. The mouth and nose can only be imagined behind the mask. Free from any kind of veil, only Borrego’s eyes sparkle when he brandishes the gun. This contains a special paint whic h the coating process engineer, with a great deal of care and experience, sprays on a metal-lic workpiece hanging on chains from the ceiling. “The par t belongs to the undercarriage of a British Aerospace 146,” says Borrego. Sweat is dr ipping from his forehead as he emerges
Shining in theAircraft flying at an altitude of 10,000 meters have to withstand a lot: the people at LUFTHANSA TECHNIK know the formula for ensuring that paint does not fade or crack under extreme conditions.
from the paint booth again and removes the respirator. “It is arduous work breathing through a mask under physical stress – one painting session lasts between 15 and 45 minutes.” Three to seven coats are applied depending on the paint system.
All-rounder above the cloudsMany things are painted in the modern world, including finger-nails, furniture, radiators, and cars. Aircraft are considered to be in a league of their own in this discipline. Time-consuming and costly processes are needed to make passenger jets shine, because aircraft paint has to withstand a great deal: “The tem-peratures at an altitude of 10,000 meters and on the ground at desert airports (such as Dubai or Phoenix, Ar izona) can f luc-tuate by up to 120 degrees Celsius,” says Maike Timm. “The paint must be flexible, as the wings move – and it has to with-stand sunlight, rain, snow, volcanic ash, and not least the deic-ing chemicals.” In other words, paint used in aviation must be an all-rounder. Maike Timm began working at Lufthansa Tech-nik as an engineer in 1988 and is now head of the paint shop, which reads distinctly more colorful on her business card: Man-ager Operations Aircraft Painting Services. She is in charge of around 40 men in the vast halls of the Lufthansa maintenance hangar. Antonio Borrego is one of them, as is his younger col-league Jan Kleineidam. “I actuall y wanted to be an aircraft mechanic; painting seemed less appealing to me.” Kleineidam has now made his previously second choice his first: “Nowadays, I know how fascinating and demanding this trade can be.” This is not least due to the fact that the paint manufacturers supply Lufthansa Technik with a wide range of pr oducts. The paints not only differ in terms of color, but also their for-mula and area of application. “Material science is extremely important in the area in which we work,” says Maike Timm. “We use between 30 and 50 different paint systems here.”
The paint on the external skin of the aircraft should look inviting and as flawless as possible – ultimately it is also about the image of the airline. Beneath the surface, on the other hand, different qualities are required, such as anticorrosive coatings or other special properties. For
Furniture in the cabin receives up to 25 coats of paint
No power: when Paul Spalek sprays an anticorrosive coating, all other work on the aircraft must be halted and the power must also be switched off
* B check: supplement to the A check; now only carried out on a few types of aircraft
MAINTENANCE INTERVALS
For the D check an air-craft is taken out of service for up to four weeks – no other means of trans-port is maintained and overhauled more meticu-lously, because there are neither breakdown lanes nor recovery vehicles on the airways. Manufacturers and supervisory authorities precisely stipulate the intervals at which an air-craft must be maintained. Lufthansa Technik dis-tinguishes between mainte-nance (up to a C check) and an overhaul (D check).
instance, on the undercarriage a thermochromic paint is used, which irreversibly changes color as soon as components over-heat, giving engineers valuable information about a potential fault. Sometimes a coat of paint is pur ely a matter of per son-al taste – and a distinguishing feature: the Lufthansa mainte-nance hangar in Hamburg is also acquainted with the so-called VIP business – the customized conversion of ordinary commer-cial aircraft into exclusive private jets. “And sometimes,” says Jan Kleineidam, “we give items of fur niture inside the cabin 25 coats of paint.”
All of these paints contain solvents which make the pro-cess of film formation and actually using them possible in the first place. They are mostly toxic and often also carcinogenic. Accordingly, Jan Kleineidam and his colleagues not only have to ensure that they are using the correct paint, but also t he
explains Spalek. “When we set about the aircraft with our spray, the power must be off.” In other words, no other tech-nicians can be at work.
Besides high-tech coatings and cor rosion prevention, specialists are increasingly decorating fuselages with adhe-sive foil and special messages. Perhaps the best known exam-ple of this in recent times is the Boeing 747 which flew the winning German soccer team back from Rio to Berlin after the FIFA World Cup final last year. Just to avoid any confusion, the aircraft bore the legend “Siegerflieger” (which translates as “Winners’ plane”) in large le tters. Six mechanics flew to Brazil specially after the final so that they could quickly apply the foil, although they also had an alter native in their luggage: if the German team had lost, the legend would have read “Danke, Jungs!” (Thanks, lads!). The Siegerflieger foil on the “ Potsdam” Lufthansa jumbo is set to be removed just before the UEFA EURO 2016 Finals.
right respiratory protection. “We essentially work with filter-ing respiratory protection, as opposed to firefighters, who use isolating respiratory protection,” says Maike Timm. At the same time, the painters also have to insert various filters in their pro-tective masks depending on the type of paint being sprayed. Lufthansa Technik primarily sources this safety equipment from Dräger.
Every gram counts!Since the components that arrive in t he paint shop f or spraying come in dif ferent shapes, sizes, and mater ials, the work is still done by hand. “The paint must be thick enough to serve its purpose, yet still applied as thinly as possible. Every gram counts in the aviation industry,” says Maike Timm. Ide-ally, the paint used to fully spray an Airbus A340 should tip the scales at 300 kilos. Ensuring that a new coat of paint is not 100 or even 300 kilos overweight therefore remains a question of intuition. At 11 a.m. Maike Timm has an appointment wit h Paul Spalek. He works in the jumbo hall on the very large air-liners. The engineer looks at the clock; the bus leaves in three minutes. The Lufthansa Technik headquarters in Hamburg is around the size of 1,000 football fields. To ensure that the engineers and technicians do not waste their working day traveling long distances by foot, a bus route connects the fac-tory gate with all the important hangars, halls, and of fices every ten minutes.
It will be appar ent to anyone who has witnessed f or themselves this huge ar ea at Fühlsbüttel Air port along with the Airbus site south of the Elbe in Finkenwerder that – besides the Elbe, containers, and all t he cruise ships – Hamburg has long since est ablished itself as Ger many’s gateway to the world of aviation. Lufthansa Technik operates more than 50 sites around the world. With 26,000 employees and 700 customers it is the global market leader in this sector. After three stops Maike Timm gets off the bus and hur ries into the large hall. Paul Spalek is standing under the huge wing of a Lufthansa Airbus which is currently undergoing a D check (see also page 17). The painter is no t applying a new coat of paint, but a g reen shimmering anticorrosive coating known as “Dinol treatment.” There is usually a two-shift operation. “But in this hall there is also a night shif t,”
Handwork:the components,
which are sprayed in a paint booth, are so different
Effective against oppressive airIn the smaller paint booths at Lufthansa Technik the employees use half masks from Dräger – ventilation draws away gas and vapors and supplies fresh air here. In the large halls, however, where anticorrosive coatings have to be sprayed directly onto fuselages and wing sections which haven’t been dismantled, the painters work with full masks. A distinction is made between single and double filters on the half and full masks. On the single-filter mask (Dräger X-plore 6570 or X-plore 4740) the filter is located centrally in front of the face, while on the double-filter mask (Dräger X-plore 3500 or X-plore 5500) the filters are located in front of each cheek. This design gives the user a better view of the area where they are working. Finally, there are also power-assisted filter systems (see page 56). Depending on the paint being used and the hazardous materials it contains, various respiratory protection filters are inserted in the system before spraying commences. Dräger supplies additional masks and filters for other application areas and hazardous materials. These essentially play a filtering role or offer light respiratory protection. There is also isolating respiratory protection, as used in firefighting technology.
Plain language: there are a number of safety notices on aircraft. These foils are also applied in the paint shop (above). Precision work on aircraft components (left)
There is always a RESIDUAL RISK wherever people are involved. Only a few are aware of this in everyday life – otherwise it would probably grind to a halt.
There is no such thing as a life with-out risk. All living creatures have devel-oped strategies to deal with an uncertain future. Plants protect themselves from the risk of being eaten – with prickles or toxins. Squirrels bury nuts in order to sur-vive the sparse winter. And people have
Tbeen thinking of ways to minimize the likelihood of undesirable events occur-ring since the beginning of time.
Yet taking risks can also be fun. The thrill that comes from not knowing exact-ly how something will end is a strong driv-er for overstepping limits, coming up with inventions, and making discoveries. Such discoverers are not just people like Chris-topher Columbus or Albert Einstein, but anyone who takes a new, significant step in their lives. A marriage can be just as
risky as st arting a ne w job or moving house. Many people are often not even aware of everyday risky situations: when driving a car or cr ossing a busy str eet, something could also go wrong.
Everyday rules of thumbThe term “risk management” is of ten associated with identifying, calculat-ing, and eliminating r isks in organiza-tions and systems by means of emergen-cy plans and checklists. Yet it starts much earlier than that. Every person is born with the skills to deal with life’s dangers and uncertainties. Even infants’ aver-sion to bitter food is a life-saving reflex, because many bitter substances are poi-sonous. “Heuristics help us to deal with uncertainty in everyday life,” says Profes-sor Gerd Gigerenzer, director at the Max Planck Institute for Human Development in Berlin, who is investigating how peo-ple make decisions in times of uncertain-ty. “Heuristics are simple rules of thumb that protect us from danger in uncer -
tain situations, for instance not crossing the road when a car within our range of vision is driving too fast toward us.” These rules have to be learnt, through imita-tion, instruction, and experience. The greater the experience, the less informa-tion required in critical situations, and the more we are able to rely on our gut feeling. In January 2009 the pilots of US Airways flight 1549 had just three min-utes to make an emergency landing on the Hudson River of f Manhattan after the aircraft struck a flock of geese. They relied on their experience – and a simple rule of thumb: when the point you want to reach rises in the cockpit windshield, you are not going to make it there.
There are risks on which most peo-ple agree. When a plane crash, tsuna-mi, or f lu epidemic claims many lives, the shock is deeply felt. The fear of such things has a lot to do with the history of mankind. “It’s not just about the fear of dying, but also about a high number of people dying at the same time,” explains Gigerenzer. “People used to live in small communities. If a large part of that com-munity suddenly died, it represented a high risk for the survivors.” This also explains why some r isks, whose effects extend over a long per iod of time, are not seen as such a big threat: a multiple car pileup on the highway causes great-er horror than several thousand traffic fatalities over the course of a year.
The differing view of risksObjective risks, which can be calculated with the help of the theory of probability on the basis of st atistical data, do not
correspond with per-ceived risks. Many peo-ple consider a plane journey to be a high risk, but har dly any-one sees a car jour -ney in the same way, even though there is a tenfold higher likeli-hood of a fatal car acci-dent per capit a and kilometer. When we step out of the taxi at the airport, the riski-est part of t he jour-ney is already behind us. Factors such as personal concern or faith in the respon-sible people or institutions play a key role when making a subjective assessment. A risk is generally deemed to be not so much of a threat when it can be t aken voluntarily and – supposedly – controlled. A free climber considers their health risk to be manageable and probably tends to have a greater fear of pesticide residue in their food, over which they have no influ-ence. Societies also assess risks different-ly. “Americans, for instance, consider it
INTEGRATIVE RISK MANAGEMENT FOR GLOBAL RISKS
Deepwater Horizon, Fukushima, or the financial crisis – these events were catastrophes with global repercussions. Since 2011, ETH Zurich has been conducting research into risks that are so complex that they could throw the world of politics, science, and business into turmoil. The models not only consider technical, economic, and ecological risks, but also political and social factors.
irresponsible to decorate the Christmas tree with wax candles, but of ten see no risk in arming their children with guns,” says Professor Gigerenzer providing a transatlantic example.
The Federal Institute for Risk Assess-ment (BfR) in Berlin conducts surveys and studies on the perception and assess-ment of risk, which often reveal a discrep-ancy between the judgment of laypeople and experts. Pesticide residue in food is generally judged to be riskier by consum-ers than specialists. Statistics and the theory of probability are mathematical tools used for planning how to deal with undesirable events. It starts with identi-fying a risk. The Robert Koch Institute in Berlin, for instance, gathers data on all reportable infections and produces digital maps in the event of an epidem-ic so that the spread can be assessed at a glance. It may look like predictability, but is merely a recording exercise in the first instance. Risk management in the event of a f lu epidemic is rather mun-dane: wash your hands, wear gloves, iso-late those affected, and be vigilant.
Sophisticated reporting systemDealing with risks in hospitals is more complex. Since January 2014, minimum standards have been in place in Germa-ny for establishing extensive error report-ing systems, which have to be imple-mented on the basis of the provisions set out in the Patient Rights Act of 2013. Dr. Maria Ines Cartes, responsible for strategic risk management and patient safety at Hannover Medical School, has established a reporting system for risks,
Successfully managing risk – with DIN EN 80001-1 The rapid development of modern technology also carries risks: IT networks in hospitals, for example, contain the documentation of various diagnostic investigations and treatments and also store and send images and medical data. The sheer diversity of medical products, standards, and configurations within medical IT networks increases their predisposition to risk.
The DIN EN 80001-1 standard, a set of guidelines, defines three fundamental protection aims which need to be considered when integrating medical products into an existing IT network:
• Safety (patient safety)• Data and system safety (protection of medical data)• Efficiency of processes (availability)
Interdisciplinary cooperation between all professional groups and organizational units within the hospital is necessary in order to implement a risk management system accordingly. “This inevitably results in a new area of activity for the IT network risk manager,” says Jutta Antwi-Schultze-Lebenstedt from the Dräger Academy. The establishment runs various seminars and training courses in the three major German-speaking countries – including one on IT security and successfully managing risks (in accordance with DIN EN 80001-1) and, building on this, the “medical IT network risk management” course leading to certification by the IHK (Chamber of Commerce and Industry).
errors, and near misses, f ocusing on errors which have been discovered in time, before an incident has occur red. They are recorded anonymously, volun-tarily, and sanction-free. This is onl y possible when people can speak openl y about the circumstances which led to the error or near miss. This blunt anal-ysis plays a key role in rectifying process-
es prone to error. “The employees are sensitized to deal with and – if f easible – rectify recurring problems as soon as possible,” says Dr. Cartes. It has been possible to bring about improvements in this way, such as clear marking of med-ication, strict checklists in the operat-ing room, or creative solutions to identi-fy non-German-speaking patients. Even though new risks are constantly emerg-ing in hospitals, an error reporting sys-tem leads to improved safety. “That is why I prefer to talk about a safety cul-ture rather than an error culture,” says Dr. Cartes.
In a world full of risks, ARMORED VEHICLES have to provide the best possible security. German ballistics authorities verify their effectiveness. There are also additional protection mechanisms, including an independent fresh air supply, which protects occupants from the ingress of smoke or irritant gas.
Text: Peter Thomas
Fortresses on Wheels
Bulletproof: this is how an armored vehicle looks after passing the test – experts from the ballistics
The noise of the shot almost casu-ally penetrates the sheet of glass in the booth. Around the area of glowing met-al currently lit up by the red spot of the laser pointer is a tiny black flower with its jagged sheet metal petals pointing menacingly upward. It is the sign of a direct hit whose projectile has bent and mangled the metal skin. This is how the experts from the Federal Ballistics Authorities in Germany test whether a material or structure meets the requi-site bullet-resistant standards under lab-oratory conditions.
Subjected to especially in-depth test-ing are civil armored vehicles: sedans and SUVs which have been reinforced with special materials to withstand gun attacks above all else. “The y are subdi-vided into ten different ‘vehicle resis-tance’ classes (VR1 to VR10), with each
Tlevel of protection defined in the BRV 2009 (bullet-resistant vehicles) st an-dards,” says Peter Häußler, securi-ty technology expert at Ulm ballistics department, which is part of the region-al authority of Tübingen. Two further authorities in Germany carry out tests of this kind – in Mellr ichstadt near Fulda and in Munich.
The reason why t hey are all con-centrated in the south of the country is obvious. After all, this is primarily where the luxury sedans and SUVs ar e built which generally serve as the basis for armored vehicles. Besides the premium
German brands, foreign companies are also among the customers. The testers fire several hundred shots at a vehicle in order to test the security concept. After many days of testing, bullet holes cov-er the hood, sides, roof, and rear of the body – cracks sprawl across the panes of glass like milky spiderwebs. But it’s not about beauty here: much more impor-tant is whether splinters or even projec-tiles have penetrated into the vehicle’s interior.
Always new risksAttacks with firearms remain the great-est risk against which armored vehicles are designed to protect. The higher the vehicle resistance class, the greater the security for the occupants. Customers who consider themselves exposed to a comparatively low r isk such as str eet crime with handguns tend to opt for mod-els with light armored protection (VR4).
Vehicles in class VR7 or higher ar e designed for higher risks (right up to terrorist attacks). But t hey are also designed to protect against har mful gases, vapors, and aerosols. No amount of armor can help here. That is why, in all their armored vehicles, every major
A self-contained fresh air system to escape the danger zone
manufacturer offers the Emergency Supply System (ESS), de veloped by Dräger and launched in 2004, – f or a fresh air supply for the driver and pas-sengers which is independent of t he atmosphere. In 2011 the company intro-duced ESS II, which offers even greater security against potential failures.
The supply of air in the vehicle com-pressed at 300 bars in compliance with DIN EN 12021 is suf ficient for sever-al minutes, providing enough time to escape the danger zone. “The system is activated by the driver at the touch of a button when needed,” explains André Huschke, head of product management in the engineered solutions division of Dräger. “This opens the shut-off valve in the compressed air reservoir, similar to how an airbag is activated.” The air then flows through a pressure regulator. An integrated metering device feeds it into a tube system and supplies the vehi-cle interior with fresh air (at a relative excess pressure of a few pascals). This in turn prevents hazardous gases from penetrating the vehicle while the win-dows and doors are closed.
The market for armored vehicles is dominated by the major automobile manufacturers. There are also a f ew
medium-sized companies which special-ize in retrofitting vehicles. A high le vel of handwork and individuality is typical of this kind of business.
This is also true of the Audi A8 L Secu-rity unveiled last year. Each car is made in Neckarsulm, takes 450 man-hours to build, and is equipped with the Dräger ESS II if required. The 5.27-meter-long sedan with all-wheel drive meets VR7 standards and cer tain sections e ven meet VR9 and VR10 standards. The car has also undergone explosion resistance testing (ERV 2010) and is considered the lightest vehicle of its kind.
A lightweight design and ar mored protection? How do those two things go together? When this technology was first developed in the 1930s, engineers really did use solid armor plates. At the time, civil vehicles for heads of state and cap-tains of industry were even fitted with folding window blinds made of steel, for Japanese Emperor Hirohito, among oth-ers – dark, but safe. Later on, special pro-tective layers were produced and then integrated into the vehicle. Nowadays, besides metal, ceramic materials, spe-cial textiles, foils, and glass fiber com-posite materials are also used.
Effect and cause: shots on the wind-shield (left) are part of the test – a gun
Security with tradition: Dräger has been supplying the
ESS fresh air system since 2004 – the second generation
has been fitted in the trunk of armored vehicles since 2011
In the case of t he Audi A8 L Secur ity, armor steel and components made of aramid and especially tough aluminum alloys help to reinforce the vehicle. It is hard to tell that it is an ar mored car from the outside.
Weak spots targeted The armored vehicles made b y every major manufacturer all shar e this impression as st andard – t he relative inconspicuousness ultimately also lowers the risk for the occupants. Meanwhile, not even the smallest detail of the vehi-cle design remains concealed from the testers at the ballistics authorities. The experts start by inspecting the vehicle in question. The observations then result in a catalog of firing points. The tech-nicians practice a kind of “reverse engi-neering” in order to subsequently verify their conclusions using brutal methods.
To this end, each point to be shot at in the course of the test that lasts sever-al days is marked with a so-called target
patch before the first shot is even fired at the vehicle. The patches mainly accu-mulate along joints and at t he height of transitions in t he bodywork struc-ture – these regions are considered to be potential targets, although patches are also placed on doors, engine hoods, underbodies, and roofs. The experts fire up to 300 shots at the armored vehi-cle – including special shooting pat-terns such as the “120 triangle” (three shots in the form of an isosceles tr ian-gle with sides measuring 120 mm) and the “multi-hit” (three shots in the form of a triangle whose bullet holes are at least three times, but no more than four times, the size of the caliber apart).
At the ballistics department in Ulm the employees do not actually handle weapons themselves, but w ork with a precision system which is equipped with laser targeting and is fired remote-ly. In order to get the test object in t he optimal position, the vehicles, some of
which are up to six meters long and weigh five metric tons, are placed on a turntable. Nowhere else in Ger many can a platform with these dimensions be found. When access to a lower or higher location is required, for instance to test the roof structure, a robot is used. The impact on the vehicle is recorded, evalu-ated, and marked after every shot using green (no penetration) and red (pene-tration) stickers. If no shots or splinters have penetrated the vehicle at the end of the test, the manufacturer receives the coveted certificate.
Besides civil armored vehicles (up to standard VR10), there are even high-er security levels which can withstand projectiles shot with considerably more force. However, the standards for such armoring usually fall within the area of military vehicle technology. Yet it is not just armies who benefit from such expertise: US President Barack Obama is chauffeured around in a limou-sine weighing eight metric tons – the armored doors alone are said to be 20 centimeters thick.
When there is danger in the airThe ESS II fresh air system creates an excess pressure in the vehicle’s interior a few pascals higher than that of the atmosphere, thereby protecting the occupants from gases, vapors, and aerosols.
Gases are substances which are in a gaseous phase at atmospheric pressure and ambient temperature. They tend to completely and evenly fill a space unless they are much heavier than air – then they concentrate on the ground, such as tear gas or the nerve gases sarin and tabun.
Vapors form during the transition of a substance from the liquid to the gaseous phase. In everyday use, mixtures of the gaseous phase of a substance and the aerosol from the liquid phase are described as vapor. Unlike most gases, vapors such as hydrogen chloride and phosgene are visible.
Aerosols make up the biggest group of volatile substances transported through the air. These include dust (microparticles from solids), mist (drops), and smoke (mostly solid and liquid particles formed through oxidization processes in conjunction with combustion gases) such as anthrax or lethal toxins such as ricin.
The risks have changed, but the frequency of the call-outs has remained the same: the FIRE DEPARTMENT in the city of Hamburg responds to around 700 calls a day – preventing fires and saving lives.
ing agents, and the entire tool kit right through to the chain saw: Clemens Wegner and Micha Zöllner carefully examine each piece of equipment on board the fire truck before checking the vehicle’s functions. Today, aspir-ing fire chief Wegner and fire chief Zöllner are working as part of the fire crew on duty from fire and rescue watch 23 in the Hamburg district of Barmbek. If they are called to a fire, they put on their breathing appara-tus – stored on the seats in the truck’s cab – on the way there. The fire de -partment (FD) in Germany’s second-
with emergency and ambulance ser vices by the administration of the British occupation zone. Accordingly, an armada of ambulances painted white (initially without a blue light or siren) was added to the red fleet of emergency vehicles. However, the two-tone color scheme of the fleet didn’t last long: when the ambulances switched to the passenger vehicle chassis based on the VW Trans-porter, the red color scheme of the fire trucks had already established itself in the ambulance service. Nowadays, flu-orescent red foil is stuck on the fire trucks and ambulances of Hamburg FD.
Among the various locations, fire and rescue watch 23 in the district of Barmbek is one of the busiest. Besides a fire unit with two vehicles, turntable ladder, and rapid response vehicle, four ambulances are also stationed here. In addition, Barmbek is home to the special unit responsible for rescuing people from heights. The watch also mans the emergency doctor vehicle and a further ambulance based at the dis-trict hospital.
Monday, 6 a.m.: the start of the shift for third watch. Jürgen Thoms gives the officers their duties for the day. Each of the colored nameplates on the
largest city responds to around 700 calls a day – at peak times there can even be more than 1,000. “From technical assistance to firefighting, we do it all,” says Zöllner. However, he and his colleagues also respond to medi-cal emergencies, because in addition to fire protection Hamburg FD also acts as an ambulance service, which is why the crew members not only have fire-fighting qualifications, but are also trained emergency medical technicians or paramedics. While a vocational qual-ification is primarily required through-out Germany for a “career on the ladder,” Clemens Wegner and Micha Zöllner had already worked as emer-gency medical technicians before opting for a career in the fire department.
Training offensive to cope with demographic changeTraining new firefighters and paramed-ics is a matter of the utmost importance for the fire department in Hamburg. It has to fill vacancies in order to be able to meet the new safety objective in compliance with the requirements stip-ulated by the Working Group of Pro-fessional Firefighting Chiefs (AGBF) in Germany relating to critical house fires. In addition, a number of older col-leagues will be retiring from active service over the coming years. “We will be really affected by demographic change – from 2017 onward we must compensate for the sharp annual rise in older colleagues leaving the service,” says Klaus Maurer, chief fire officer of Hamburg Fire Department. “Although we have taken an initial step in the form of a training offensive, the three-year training course to qualify as a paramed-ic will probably provide a new route into the career, while many emergency medical technicians will undertake fur-ther training to become paramedics.”
The combination of fire department and ambulance service accounts for the high number of call-outs in Hamburg. This has been the case since 1946 when the city was given the task of dealing
Watch changeover in all weathers: at just after 6 a.m. third watch takes over responsibility for the fire and rescue vehicles in Barmbek (left). Among them are the firefighters Micha Zöllner (left) and Clemens Wegner
On the safe side: the fire and rescue vehicles at
Barmbek are carefully checked after each shift changeover
Fully loaded: the Hamburg fire truck is tailored to the needs of large cities
homes and highly efficient gas extin-guishing systems on ships.
In Barmbek fire station the fire-fighters are attending another training course this morning. The timetable also includes a lesson on the use of Dräger tubes for measuring hazardous materials. Then Micha Zöllner talks about his experience while working on the ambulance service with a patient suspected of having contracted Ebola. Itinvolved administering care in an in -fection protection suit, communicating via a rescue coordination center with a tropical medicine doctor, using the fire department’s infection ambulance, transporting the patient to a special-ist hospital, and decontaminating the medical workers. This is no rare oc currence in a city like Hamburg with almost two million residents. Densely populated areas, 30 ports, major indus-try, and a wide-ranging transport infrastructure are the reasons why the work of Hamburg Fire Department is so demanding.
Besides the 2,400 professional offi-cers in the fire department, a further
clipboard corresponds to a worker; the individual nameplates are assigned to one particular vehicle. The two fire-fighters assigned to the fourth ambu-lance, who are also manning the equip-ment vehicle today, are the exception here. The vehicles and all the equipment – from the turntable ladder to each individual tool – are inspected before breakfast.
Working in infection protection suitsFour chairs in the breakfast room remain empty this morning. Two of the ambulances have already been called out. Between the muesli and the bread rolls the bell rings again and the light signal for the third ambulance illumi-nates: the next medical emergency. Two years ago Hamburg FD was called out more than a quarter of a million times within the space of twelve months for the first time – more than 85 per-cent of the call-outs were attribut-able to the ambulance service. Major fires in buildings and aboard ships, once the most spectacular missions, have dropped significantly. Among other things, this is due to the regula-tions prescribing smoke alarms in
More than a quarter of a million call-outs in 12 months Identifying
2,500 voluntary firefighters from 87 volunteer fire departments and six works fire departments (including two air-port departments) also play a key role in fire protection in the city on the Elbe. The fact that the river occupies a special position in their work is not solely due to the ports – this is the responsibility of the professional fire department – and the two fireboats, but also the new Elbe Tunnel. Both watches of the Elbe Tunnel Fire Department, previously part of the building authority, have been manned by professional firefight-ers since 2001.
State of emergency in the city center Sometimes the city itself is the cause of special kinds of risks. This also goes for the violence committed against emergency workers, with which the ambulance service is confronted at night in particular. According to a recent study, the typical attacker is a man aged between 20 and 40 under the influ-ence or alcohol or drugs. The pheno-menon is nothing new, as the classic book Florian 14: Achter Alarm de monstrates. It was written in the mid-1960s by journalist Hans Georg Prager and is a factual report on the work of the fire department, document-ing the experiences of a firefighter on active duty – such as during call-outs on Friday evenings when wages were blown and alcohol flowed.
Yet the fire call-outs also evoke parallels with the past, although the spectacular ship fires on bulk and general cargo vessels have now given way to call-outs on container ships or at port facilities. And the great fire of Hamburg, which raged for four days in May 1842 and destroyed a large part of the historic old quarter, resonates with every call-out anyway. After all, it was this catastrophe that led to the professionalization of fire protection in the city – and the founding of the professional fire department on Novem-ber 12, 1872.
HAMBURG*1,752,000 RESIDENTS
11,500 CALL-OUTS TO FIGHT FIRES ANNUALLY21,750 CALL-OUTS FOR TECHNICAL ASSISTANCE ANNUALLY 19 FIRE DEPARTMENT CALL-OUTS ANNUALLY PER 1,000 RESIDENTS
23PROFESSIONAL FIRE STATIONS 87 VOLUNTARY FIRE STATIONS
1 PROFESSIONAL FIRE STATION** 3 VOLUNTARY FIRE STATIONS
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313CALL-OUTS TO FIGHT FIRES ANNUALLY
554 CALL-OUTS FOR TECHNICAL ASSISTANCE ANNUALLY
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Heavy load Whether in Hamburg or the Hessian city of Rüsselsheim, German firefighters have just as much to do in built-up areas – no matter how their work is structured.
The Dräger DrugTest 5000 can reveal if someone is under the influence of drugs in a matter of minutes. Its precision is based on SPECIFIC ANTIBODIES – they fit the intoxicants like a key in a lock.
Drug use is a social reality. Many people cannot and no lon-ger want to go without the mind-altering kick, even though it may be at the cost of their health sooner or later. According to a re-cent report published by the Federal Government, one in four Ger-mans aged between 18 and 64 has used cannabis; 319,000 Ger-man citizens are dependent on illegal drugs. The accident statistics from the Federal Statistics Office are also very clear: in 2013 no less than 3,896 road accidents involved people under the influ-ence of drugs; 1,913 people were injured, 457 of them serious-ly. Several dozen people died because they or others had taken drugs shortly beforehand.
If law enforcement officers wish to test a person’s fitness to drive, it has to be done quickly and the test must provide informa-tion about the current situation. “The police have to measure drug
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Cannabis sativa is the Latin name for
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use at that moment in time, not past use,” says Rainer Polzius, re-sponsible for the development of the DrugTest 5000 at Dräger. “It’s not about establishing whether a driver was fit to drive yester-day or last week, but whether they are fit to drive now!” The de-vice tests saliva and not blood or urine. Drugs do not last long in saliva, but can be detected in urine for a considerably longer peri-od of time. Tetrahydrocannabinol (THC) COOH (carboxylic acid), the main metabolite of THC, can even be traced weeks later. Sa-liva, on the other hand, is easy to obtain during a roadside test. In addition, the sample cannot be manipulated – any attempt at de-ception would be immediately noticed.
The saliva test is based on an antigen–antibody reaction, similar to a pregnancy test. Antibodies are an integral part of immune di-agnostics due to their high specificity. You could also call them molecular heroes. The immune system defends itself against all impurities with antibodies and does so very precisely, only form-ing the kind of antibodies which precisely match the foreign mod-els. If antibodies encounter a specific antigen, an immune complex forms. The specific identification is also the reason for the hero status of the antibodies, because this is the basis for the broad value of this molecule class. In laboratory diagnostics, antibodies are used to detect the presence of proteins, hormones, toxins, or infectious agents. In medicine, chronically inflamed conditions and cancer are treated with antibodies, because they precisely target the area requiring therapy. Vaccines are also based on the effica-cy of antibodies: in active immunization, an immunological memo-ry is built up out of antibodies produced by the person’s immune system; in the passive form doctors help in an acute situation by administering suitable antibodies directly into the blood. The he-roic act is always the specific identification of the antigen.
The DrugTest 5000 uses drug-specific antibodies to prove the presence of more than half a dozen drugs: amphetamines, meth-
Antibodies are molecular heroes when testing for the presence of drugs
amphetamines, opiates, cocaine, benzodiazepines, cannabis, the heroin substitute methadone, and the synthetic narcotic ketamine. The only problem is trying to differentiate between the remnants of a poppy seed roll and heroin in the saliva, which is also extreme-ly difficult chemically. Drug-specific antibodies react to a group of active agents, allowing several representatives of the same class of drugs to be identified at the same time. The saliva test consists of a sample collector (the actual test cassette with the testing strips), a buffer cartridge, and the analysis device itself. The test cassette contains five strips, each with two positions to ascertain the presence of drugs. “It is possible to prove the presence of up to ten intoxicants,” says Rainer Polzius. “At the moment, eight posi-tions are occupied, but we are continually examining the relevance and technical possibilities of proving the presence of new drugs.”
Competition as a testing principleThe testing strips are made from a porous membrane; the test it-self functions automatically. Once the saliva sample, test cassette, and buffer cartridge have been inserted into the analysis device, the internal temperature is brought to the optimal level and the sali-va is mixed with the buffer solution contained within the buffer car-tridge. The testing strips are then dipped into this mixture and the liquid migrates in one direction across the strips by capillary force. This is when what is also known in technical terms as the “later-al flow test” begins: the drug-specific antibodies are positioned on the membrane just after the starting point; located in the middle of each testing strip is a small amount of the drug whose presence is to be tested. When the mixture of saliva and buffer solution moves
Dräger DrugTest 5000 – the presence of eight commonly abused substances can currently be established using specific anti-
bodies. These include cannabis and amphet-amines, the most commonly used drugs,
A little lexicon of moleculesLiving beings protect themselves from foreign substances and pathogens using their immune systems. Its most important protagonists also help in the area of immune diagnostics.
Antigen = A substance identified by the immune system as foreign and responsible for the formation of antibodies.
Antibodies = Proteins formed by the B cells of the immune system. They identify antigens and help to fend them off as part of an immune response.
B cells = Immune cells which are part of white blood cells and form antibodies.
B cell clone = A B cell clone is a group of identical B cells produced by the division of one single B cell.
Epitope = The part of the antigen identified by the antibody and to which the antibody specifically attaches itself.
Immune diagnostics = The area of diagnostics which identifies substances or molecules using the high specificity of an antigen–antibody reaction. This is established by means of markers on the antibodies. Monoclonal antibodies are generally used.
Monoclonal antibodies are produced by a single clone of B cells and identify just one single epitope of the antigen. Monoclonal antibodies are identical among each other.
Polyclonal antibodies are produced by many different clones of B cells and identify various epitopes of the antigen. Polyclonal antibodies are a mixture of various antibodies.
Lock and key theory = The principle which states that two or more complementary structures can only fulfill their biological function if they fit together precisely. The identification of an antigen by an antibody follows this principle.
Risk: new drugsThe drug market is always being flooded with new psychoactive substances. These are derivatives of approved medication, natural substances, or compositions which the pharmaceutical industry synthesized at one point and then later abandoned. None of the products have ever been rigorously tested. The side effects, toxicity, and dispersal in the body are only gradually learned from the emergency rooms or autopsy reports in the area of forensic medicine. Dealing and possessing the new drugs is a criminal offense if they are covered by the German Controlled Substances Act (BtMG). For some of them this is the case; for many of them it is not. This is either because their existence is not even known or because the process takes time. As soon as the
substances are listed in the BtMG, drug makers modify the basic chemical structure and thus circumvent the law. The whole thing is like the tale of the tortoise and the hare, in which the drug makers (mostly) have their noses in front. One or two new designer drugs appear every week.
across the testing strips, the drug-specific antibodies are released from the membrane and taken with it. If the saliva contains drugs, the molecules immediately combine with the relevant antibody. This is then no longer able to bond with the reference substance locat-ed in the middle, because it is already occupied with the drug mol-ecules from the saliva sample. If there are no drugs present, the fol-lowing happens: the antibodies attach themselves to the reference substances located in the middle, because they have not reacted with the drug molecules from the saliva. The test principle is thus a competing reaction. The visible proof is in the form of a marker on the drug-specific antibodies. This involves gold particles which emit light of a certain wavelength as soon as they themselves are exposed to light. If the analysis device registers a light signal, the antibody has attached itself to the drug in the middle of the testing strip. This means that no drug molecules are present in the saliva. If no light signal is registered, this is almost certainly proof of the presence of drugs. There is thus an inverse relationship between the drug concentration in the saliva and the signal strength via the antibody bonded in the middle of the testing strip. After five min-utes, the results for seven drugs are available – all except canna-bis. Testing for the presence of tetrahydrocannabinol takes around three minutes longer. The DrugTest 5000 is a presumptive test de-vice which predicts current drug use with a high degree of prob-ability. Subsequent tests have to be performed in the laboratory for confirmation of the presumptive test. Laboratory analysis is neces-sary due to the potential for cross-reactivity or mouth contaminants.
Drug tests in the workplaceThe saliva test can not only be used to assess a person’s fitness to drive, but also to test drug use in the workplace or in jails. In Ger-many, drug tests in the workplace are a rarity, because they infringe on the personal rights of the employee. At the same time, there are many professions with a high accident risk where drug use among employees can have devastating consequences. These include com-
Rapid test in less than ten minutes
mercial drivers, pilots, forklift truck drivers, and crane operators, as well as the nuclear energy and (petro)chemical industries. “Drug tests in Germany are voluntary or clearly governed by an employ-ment agreement,” explains Rainer Polzius. “Following a judgment by an industrial tribunal in Hamburg, however, reasonable suspicion is not necessary if the activity is associated with considerable danger and the fitness for duty cannot be established in any other way.” It is different in the United States, Australia, and other European coun-tries. In these countries safety comes before the personal rights of employees. Ultimately, most people’s drug abuse goes unnoticed, be-cause they do not conform to the common cliché of a drug user.
It contains fi ve lateral fl ow drug test strips aligned next to one another. The open ends soak up the mixture of saliva and solvent. The direction of travel is from top to bottom in this picture. The dark blue fi elds represent the drug-specifi c antibodies. The light blue lines show the reference substances which compete with the drugs in the saliva for the marked antibodies.
Time taken to prove presence of drugsIntoxicants can be detected for different lengths of time in blood, saliva, and urine. The bars represent the time in hours. With regular use, THC-COOH can be detected weeks later in a urine sample.
Negative testWith no drugs in the saliva the marked antibody attaches itself to the reference substance in the middle. The signal represents a negative drug test.
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sPositive testDrugs in the saliva attach themselves to the marked antibody and prevent it from docking in the middle. The missing signal repre-sents a positive drug test.
Every year fire crews in Germany put out around 200,000 fires. Once their job is done, experts work on behalf of insur-ance companies and district attorneys to try to reconstruct the outbreak of the fire from the charred remains. Experts like Kai Günther, an assessor from the Institute for Damage Prevention and Research (IFS) in Kiel. The q ualified engineer is responsible for establishing the cause of fire and damage in the area of electrical engineering.
What he is confronted with at var-ious crime scenes doesn’t look nice: mostly charred and stinking appli ances which have melted be yond all recog-nition – such as this hair dryer, whose original shape can no longer be dis-cerned. At this point in time Günther is still unaware that this will be an inter -esting case which he will bring to a suc-cessful conclusion.
At first it all appear ed to be t he result of a short circuit. The fire depart-ment was called out as t he bathroom of a house smoldered. The family was woken in the night by crackling nois-es and immediately ran into the street, because the living ar ea was already filled with thick smoke. When Kai Gün-ther investigated the scene he was tak-en aback – a hair dr yer was blamed for starting the fire.
Yet how could a short circuit occur if the appliance wasn’t even switched on?
E
A fire is sometimes like a crime story: who is the culprit? What exactly was the cause? The investigations are not just about convicting potential arsonists – the findings often have an impact on FIRE PREVENTION.
Text: Regina Naumann Photos: Sibylle Zettler
The family was asleep; nobody had used the hair dryer beforehand. Microscopic examination confirmed the short cir-cuit; the melted wires could clearly be seen behind the main switch. Kai Gün-ther was unable to clear up this case, because the remains of the hair dryer were destroyed. He had to file it away. The insurance company put the dam-age at 135,000 euros.
Manufacturer launches a product recallThe following year another hair dr y-er caught f ire – once again K ai Gün-ther examined the charred remains and once again there was found to be a short circuit a few centimeters behind the heating element. “This time we had better luck,” says the assessor. “Half of the switch was still intact, which meant the cause could be anal yzed more pre-cisely.” A comparison with a function-ing hair dr yer brought the solution.
DAMAGE LEADS TO WISDOM
The fire department is not only there to put out fires: “We are also involved in fire prevention,” says Thomas Grams, press spokesman for Hamburg Fire Department. In 2013 alone there were more than 9,000 such preventive cases. Fire prevention measures also build upon the findings of the fire inves ti ga- tion. In the United States, for instance, the first sprinkler systems were devel-oped as long ago as 1874 to ensure that fire water was available quickly.
Charred: the remains of the heating element put investigators on the right track after the second hair dryer fire
“Due to the melted plastic housing, the switch stuck firmly in place at t he time of the fire – precisely between the on and off position.” With fatal conse-quences: “Even the slightest of move-ments could slide the switch out of this intermediate position into the on posi-tion, perhaps as a result of the spring tension giving way.”
And that is exactly what happened. The hair dryer had switched itself on – which was possible in t he first place because it was still plugged in. Thus movement was once again invol ved. It appeared to be a design f ault, because
This was enough mo tivation for Kai Günther to investigate further. “I bought another hair dryer of this brand and it had a thermal cutoff which automati-cally switched off the appliance.” But Günther still also had t he two hair dry-ers which he had bought ne w in t he course of t he earlier investigations. After examining them under the micro-scope, it turned out that the thermal cut-off was missing from the older models. The cause of t he fire could therefore clearly be attributed to the faulty appli-ance, which was able to switch itself on and had no thermal cutoff. It was then that the manufacturer recalled all older models and brought a new product onto the market – with the necessary safety improvements.
Search for clues in the laboratoryOne in three cases of fire damage hith-erto solved in Kiel can be traced t o faulty electrics, according to managing director Dr. Hans-Hermann Drews. Yet almost one in ten f ires is started inten-tionally. If the fire department, police, or eyewitnesses suspect arson, Dr. Dag Leine is r egularly called upon. The chemist firstly checks the scene of the fire for traces of f ire accelerant using the photoionization detector (PID).
“The device uses a small pum p to draw in the air at the scene of the fire and then analyzes it to see whether it contains volatile organic subst ances such as petrol or similar. This gives me an initial idea of what may have st art-ed the fire,” explains the expert. “How-ever, volatile combustion products can
the sliding switch could not be def i-nitely fixed in the right position. The fire investigator was now able to fur-nish the insurance company with more information. “We also f ound small remains of plastic whic h allowed us to identify the CE marking and manu-facturer under a microscope.” Yet this was by no means t he end of the case, because the manufacturer disputed the cause of the fire and referred to the findings of the testing institute. There was said to be a t hermal cutoff fitted to make it impossible for the hair dry-er to overheat.
33 ELECTRICITY
23 OTHER/UNKNOWN
16 HUMAN ERROR
10 OVERHEATING
9 ARSON
3 WORK INVOLVING FIRE HAZARDS
3 OPEN FIRE
2 EXPLOSION
1 SPONTANEOUS COMBUSTION
0 LIGHTNING STRIKE
Causes of fire (in percent)
STATISTICS ON CAUSES OF FIRES
A third of the 1,200 cases of fire damage investigated by the Institute for Damage Prevention and Research in Kiel in 2013 show electricity to be the cause. There are no cases of lightning strikes, because such damage is relatively easy to identify and generally does not result in an investigation.
Searching for traces – on a micro scaleWhen arson is suspected, the presence of highly inflammable liquid residues often has to be proven. A photoionization detector (PID) provides initial evidence of a criminal act. The device draws in ambient air through a measuring chamber using a pump and exposes it to the UV light of a high-intensity discharge lamp. If there are substances in the air which can be ionized by the UV rays, a current flow is pro -duced in the electrical field of the measuring chamber. This is amplified and shown on the display of the device as a concentration. The Dräger Multi-PID 2 measures volatile organic compounds. With a 10.6 eV UV lamp it measures from 0 to 2,000 ppm (parts per million). A gas library containing several dozen materials is stored in the device; a further 60 can be identified and exchanged in the library. It is suitable for a wide range of applications: screening earth, water, and gases in containers, searching for leaks, and taking measurements in closed rooms.
also register a positive r esult, so t he PID sample would not yet stand up in court.” The actual proof is established in the laboratory. This is where the often tiny residues of the suspect fire debris is enhanced in a substrate before a gas chromatograph separates the individual materials from each other and analyzes them in a mass spectrometer. “We have between 50 and 60 reference substances in our chemical database,” says Dr. Dag Leine. “And it is continuall y growing, because fire accelerants and their com-position are constantly changing.”
This makes it difficult and time-con-suming to identify a certain product, as in the case of t he detective commis-sioned by an insurance company, who bought 20 different types of barbecue lighter fluid in all the home improve-ment stores. One of them was actual-ly identical to the fire accelerant used. Besides creativity and painstaking atten-tion to detail, there is also a little luc k involved.
Constant companion:
clues to how a fire started can often
only be found under the microscope
Short circuit: Kai Günther, fire investi-
gator, explains how he established the cause of
the hair dryer fire
library. It is suitable for a wide range ing earth, water, and gases in for leaks, and taking ed rooms.
For centuries scholars argued about which evil forces ruled the depths of the mountains. It was said to be dragons that suspiciously hoarded their trea-sures. Anyone who disturbed their peace was destroyed with a huge blaze of fire or with the miasma of their stinking breath. Dragon sceptics on the other hand, mostly theologians, were certain that it was demons up to no good in their tunnels and shafts. Georgius Agri-cola (1494–1555), the first German mineralogist, whose book De re metallica remained a standard text for two cen-turies, sought a compromise. He contest-ed that although the strange beings underneath the mountain were indeed living creatures, they were not spir -itual creatures. He also saw supernatural forces and proved it with details of a gory attack: “There was one in Annaberg
F
Firedamp explosions used to be considered the acts of monsters, gods, and demons. Nowadays, they answer to the name of METHANE.
Text: Silke Umbach
which killed more than 12 workers […] with its breath.” Wherever people were involved in mining, they were confronted with sinister goings-on – with fatal risks for which there was no explanation.
Heaven forbid it should ignite!The real source of the alleged dragon fire was first revealed by Thomas Shirley in 1667: methane – a simple hydro-carbon (CH4) which makes up the cru-cial, combustible part of the mine gas. It is present in widely varying concentra-tions in all coal seams. Methane-rich storage facilities require maximum safety measures. If mine gas mixes with fresh air, firedamp can form. If this mixture ignites, fireballs rush through tunnels and shafts, followed by afterdamp from the explosion, which (due to incom-plete combustion) contains toxic carbon monoxide. Those trapped by it are threatened by poisoning and sudden death. Only a self-rescuer, which should be carried by everyone when below ground and which catalytically eliminates carbon monoxide or works indepen-dently of the circulating air depending on the operating principle, offers a chance of escape.
The deadly methane formed at the same time as the coal in marshes and wetlands around 300 million years ago.
At the time, vast forests in the Ruhr region became marshy and this led to the formation of turf within which “methanogens” lived. Their anoxic ener-gy metabolism created the waste prod-uct methane. Then came the sea, which covered the marshes and stayed for millions of years before retreating. After this came the coal seams in which the turf gradually dried out and changed firstly into brown coal and then black coal, trapped under the marine sediment along with the methane – in caverns and pores, as gas bubbles or locked in the coal; up to 30 cubic meters per metric ton! It rests under the bedrock like a sleeping dragon. And this is precisely where the risk lies: there is a great deal of energy stored in the meth-ane molecules, which can be released when combined with oxygen. A methane mix of between 4.4 and 16.5 percent of the air volume can cause an explosion, assuming something ignites it.
Nightmare for all minersKen Follett, the bestselling author from the coal-rich country of Wales, describes this very accurately in Fall of Giants, the first book in his 20th century trilogy – including the shock wave, which is initially felt as a massive jolt before it promptly flashes back. When methane explodes it increases its volume eleven-fold. Following the reaction with water and carbon dioxide the gas cloud then contracts just as noticeably. The scene from Follett’s novel is set a few years before World War One. Hundreds of thousands of men earned their living
Keep the air clean and ban ignition sources – otherwise escape is the only option
Help for the helpers: in 1906 rescuers rushed from the Ruhr region to northern France with their new Dräger breathing apparatus – a firedamp explosion claimed more than 1,000 lives in a coalmine in Courrières
ries.” In the same tone it could also be said that his career had a short half-life.
Nowadays, risks underground can be managed more elegantly. Anyone who has ever been down there will have noticed the yellow boards displaying measurements of current conditions in a number of places. They show the methane content in the air. It is con-sidered to be “pure” if the CH4 content is less than one percent, way below the explosive limit. If the methane con-tent rises, the conditions are consid-ered “impure” – and the figure must be reduced again. This is made possible by ventilation technology: with fresh air, thanks to automatic management of the ventilation system and continuously active gas sensors. Keeping the air pure is the number one priority in prevent-ing firedamp, along with ensuring that ignition sources are kept well away! Firedamp explosions only occur when sparks or flames ignite them.
If this does not happen, there is time to take countermeasures if meth-ane is discovered. Accordingly, miners do not wear synthetic fibers which could become statically charged; their work equipment is protected against sparks and electric arcs. Once miners have passed through the lamp room and put on their self-rescuers and miner’s lamps, all forms of fire are prohibited. The lamp on the helmet has been electric for a long time, but this hasn’t always been the case. Naked flames provided the miners with light for cen-turies and claimed the lives of many. The first safety lamps were introduced
underground at the time. The miners descended ever deeper in order to reach the rich seams from which the coal crackled and fizzed. “The moun-tain is creaking!” they used to say. Sta-tistics compiled at the time were also very clear: in 1861 there were 32 fire-damp explosions; 30 years later there were as many as 90. The mining acci-dent in which Follett’s Welsh miners are involved is just a few years apart from the worst catastrophe in the his-
tory of European mining: in 1906 more than 1,000 lives were claimed in the commune of Courrières in northern France. Picture postcards also show German miners who – equipped with Dräger breathing apparatus – joined in the rescue efforts in the toxic after-damp of the explosion. In the end there were around 600 survivors. Lessons were learned in Courrières: the immense force of many explosions underground is caused by the interaction of the high-ly inflammable methane with another dangerous source. Although this alone can cause an incredible amount of damage, it is further exacerbated when a firedamp explosion ignites coal dust. This can build up in many places in a poorly maintained mine.
Strict fire ban Centuries of experience and intensive research have now made it possible to systematically reduce firedamp dangers underground. At times people them-selves didn’t shy away from the macabre procedures involved. Once upon a time a “fireman” was sent ahead, clad in a wet cloth and carrying a stick, on the end of which a candle burned. His mission: to burn off built-up methane. “Aside from the spectacular reaction rate, this method had its merits,” notes methane expert William Tonks with his dry British humor. “The process was quick, cheap, and very efficient. And although they didn’t know it at the time, it was also eco-friendly, but that was probably of little interest to the fireman who had his own more immediate wor-
Complex technology and applied chemistry can prevent accidents
at the start of the 19th century. The gaso-line flame in the lamps was protected from igniting in firedamp by a glass tube and finely woven wire mesh. One ben-efit of this design was soon discovered: it was able to indicate the gas content in the ambient air; in dangerous areas the flame’s appearance revealed the methane concentration. Thus the min-er’s safety lamp was discovered, effec-tively the first ever personal gas detector. It is still in use in a number of coun-tries, complemented by modern electro-nic sensor technology.
How do you tame a dragon?Despite complex technology and high-ly advanced knowledge in the areas of chemistry and physics, terrible min-ing accidents are still happening – like the one in New Zealand in November 2010. A huge methane explosion killed 29 miners; only two were able to escape. In the days that followed, rescuers who had rushed to the scene looked help-lessly on as the mine exploded a second, third, and fourth time. They couldn’t go underground – an exploratory hole drilled at the site where the victims were presumed to be located revealed an atmosphere of 95 percent methane, otherwise predominantly carbon monox-ide. They had to abandon all hope.
The evil dragons from the old stories still reside under the mountains. Only the best technology and the greatest of care, which, according to the report published by the independent investigation com-mission in New Zealand, was ignored in certain respects, can contain them.
CLIMATE
A COW
EXPELS
UP TO 200
LITERS OF
METHANE
A DAY.
To protect the atmosphere
it is better to utilize
the mine gas than let it escape.
Methane is a greenhouse gas
and almost
30times more
potent than carbon monoxide. CH4
IS THEFORMULA FOR
METHANE.** It consists of carbon and hydrogen.
Methane was discovered in 1667. In 1772 it was established that it is the result of rotting processes: alchemists
described it as “swamp air.”
When methane burns to produce carbon dioxide and water, a typical
They are like the minds of gas detectors: electrochemical sensors, which identify hazardous substances and measure their concentration in order to then raise the alarm and PROTECT HUMAN LIFE. They can be produced in particularly small dimensions – mostly by hand.
Text: Nils Schiffhauer Photos: Patrick Ohligschläger
They look like confetti in a black-and-white film, yet they could save lives: the electrodes for gas sensors are cut from a paper-thin plastic foil using a special hole punc h. The foil is made from the fluorocarbon PTFE (polytetrafluoroethylene) and plays a key role – its microporous structure repels mois-ture but allows gas and vapors through.
“The electrode is the core element of our electr ochemi-cal sensors,” says Axel Silz, who oversees production of sev-eral hundred thousand sensors of various shapes and sizes (for a wide range of gases) in Lübec k every year. A few dozen employees are involved in the process: “It takes about a year of training to learn how to assemble all 140 different types – virtually blindfolded,” according to Silz’s observations. A retail salesman by trade, Silz is also an example of how the company spots and nurtures talented people and appoints them to the right positions. Among other things, this can be seen in t he fact that the staff fluctuation rate in this division is practical-ly zero. Many years of experience is needed in the production of these sensors, the smallest and most modern of which (type: XXS) could be hidden behind a headache tablet. It is made up of a number of individual mec hanical parts and houses an electrochemical laboratory able to robustly withstand environ-mental influences. The company itself has had experience in
the production of electrochemical gas sensors since the 1970s and holds a number of related patents.
The sleuths, which are as sensitive as they are reliable, are used in the area of mobile and fixed gas detection technology, which in turn protects people from the effects of carbon mon-oxide, nitrous oxide, and other hazardous substances – includ-ing explosive gases. With a catalytic process the electrochemi-cal sensors use the reactivity of these gases. They are designed in a similar way to a battery or a capacitor: a nonwoven fab-ric impregnated with a conducting liquid and a tiny amount of sulfuric acid separates the two electrodes from each other. Certain gases cause a chemical reaction as a result of the spe-cific structure and chemistry of electrodes and electrolyte, gen-erating a current between both electrodes. An electronic cir-cuit fitted downstream within the gas detector permanently measures the current and analyzes changes – until it gives an acoustic and visual warning.
What is already fascinating in the laboratory must func-tion just as reliably during oil exploration activities in the per-mafrost of Alaska as in gas liq uefaction plants in the searing midday heat of the Gulf region, on drilling rigs with all their vibrations, and in space – because sensor s designed to detect hydrazine are also built in Lübeck. This highly reactive liquid is used as an efficient rocket fuel but is extremely carcinogen-ic, which means that reliable gas detectors are indispensable on the ground in the area of space travel –NASA also relies on Dräger sensors here. And the element at their heart starts life as a sheet of off-white PTFE foil no larger than a piece of A5 paper, which is carefully stored in a protective environment to keep the dust away.
Various precious metals in each electrodeIn the next step a speciall y prepared mixture, which is freshly blended on each occasion, is pr inted onto the foil. It contains various precious metals such as platinum, gold, and ruthenium. “This mixture,” explains Axel Silz as he holds a small laboratory beaker and its blackish-gray contents with a honey-like consistency up to the light, “only retains its properties for a short period of time. Af ter that, the next batch is mixed (according to a special recipe) by chemical
laboratory assistants, ensuring that it corresponds exactly to the gas being detected.” It goes without saying that every pro-duction step is documented. The batc h of mixture used, for instance, can be traced from the number that is later print-ed on the sensor.
Using a spatula, the mixture is applied ver y thinly to the foil, which, once printed, is peppered with a number of dots; several hundred of them fit on the A5-sized surface when elec-trodes for the smallest (XXS) sensors are produced. The elec-trodes for sensors used in fixed gas measurement technology are much bigger and there are also designs other than circular, as in the case of double electrodes. The foil is weighed before-hand and weighed again af terwards to check whether each electrode point really has received precisely the desired quan-tity of the mixture. The printed sheets of foil are then “baked” for several hours and the individual electrodes are cut out of the foil – by hand and with an eye so precise that not even the tiniest irregularities on the surface or minimal discoloration escapes the inspector’s attention. “We immediately put any rejects in the special waste for recycling,” explains Silz. After
Chemical reaction on the measuring electrodeCO + H2O CO2 + 2H+ + 2e-
Chemical reaction on the counter electrode½O2 + 2H+ + 2e- H2O
How the sensor sleuthsThe principle: the air passes through the membrane with its filter function and reaches the measuring electrode. Like the counter electrode, it is embedded in an electrically conducting liquid (“elec-trolyte”). This allows a current to flow be-tween them, which is analyzed (“dis-play”). Filters and gas-specific coatings ensure that certain gases cause a reaction on the electrodes. This alters the voltage between them. The change in voltage is an indication of the concentration of the gas in question.
Each sensor is painstakingly tested, every single one
all, they contain various precious metals, which is why it is important to reclaim them.
While the electrodes are made in this way, the other ele-ments of the gas sensor are simultaneously prepared. In the case of the XXS version a plastic casing later sur rounds the sensor so that just the uncoated side of t he foil is in contact with the environment. In contrast, the coated side is in con-stant contact with the electrolyte – irrespective of the position within the gas detector. Further foils partially filter the exter-nal air. These include selective foils, which, in the event of a mixture of gases, block the gases for which the sensor is not designed, yet could also impair the signal of the gas in ques-tion (“cross-sensitivity”).
Dandruff-like bouldersThe gold contacts for the electrical connection with the gas detector are initially pressed into the resin mold of the sensor. This is then connected to a few micrometers of thin platinum wire, whose shock-resistant spiral design ensures contact with the electrodes. Specially shaped nonwoven fabrics are insert-ed alongside the electrodes. This assembly is also per formed manually under the microscope with the help of two pairs of tweezers – a focused and almost meditative task which affects even the breathing of the employee. “It goes without saying that this work can only be done in a clean r oom,” says Axel Silz. “Even if just one f lake of dandruff falls onto the sensor, the foil bulges in this microscopic world as if it were bearing the weight of a boulder.”
A sealing compound is spread along the edge of the sensor. It remains paste-like and prevents the electrolyte from leaking
Rigorous testing: the somewhat bigger sensors for fixed gas detectors are tested under an extractor hood with standardized reference gases
Delicate work: up to 140 different sensors can be produced in Lübeck
CO moleculeSample gas, penetrates into the measuring electrode
CO2 molecule
Reaction product, passes out of the measuring electrode
H20 molecule
Element of the electrolyte
H+ hydrogen ionPositively charged because it is missing an electron
through the edge of the cover, which is pressed into place in the next stage of the process. There is a tiny hole located in it, through which the electrolyte is poured until the now almost finished sensor is around a third full – most raindrops are big-ger. As soon as the hole is sealed, general data (type, use) and individual information (such as the batch number) are print-ed on it. Outwardly the sensor is now finished and fully func-tional – for between 12 and 60 months depending on the type and what it will be used for.
Hundreds of thousands of sensors per yearIt is now time for the targeted aging process (“running-in”). This takes place at a specif ic temperature and humidity and lasts between 12 hours and four days. Only afterwards it is possible to verify whether the sensors meet the promised spec-ifications. To this end, each of the several hundred thousand sensors produced every year is exposed t o the corresponding test gas and its reaction measured and documented over a cer-tain time period. The sensors then leave the production facil-ities, which are efficiently managed using the kanban system. “We produce components here like in a factory – this isn’t pos-sible without sound judgment, experience, and manual dexter-ity,” summarizes Silz. Most of the sensors end up being used in the production of the company’s own gas detectors. They are used in various applications. These not only include mobile and fixed gas measurement technology but also Alcotest devic-es as well as emergency and transpor t ventilators – for extra safety made in Lübeck layer by layer.
Production with sound judgment,
experience, and dexterity
A good nose: Axel Silz oversees the production of the electrochemical sensors. He himself appears to have the right sensors for ensuring high quality and good atmosphere through out the team
Colorful mix: the XXS sensors designed for different gases signal the detected hazardous sub-stance via their three gold pins on the end device
At a GlanceDräger is everywhere, also in this magazine. Here is an overview of the DRÄGER PRODUCTS in this issue – in the order they appear. Each product has a special QR code which can be scanned with a smartphone or tablet. The relevant product page will then be displayed. If you have any further questions about a product, send us an e-mail stating the code to: [email protected]
EVITA V500:intensive care ventilator for treating adult patients.Code: DR111#4
Page 4
X-plore 3300:protection and comfort – this half mask offers both.Code: DR111#5
Page 5
X-plore 5500:full mask for use in environ-ments where greater respiratory protection is required.Code: DR111#19
Page 19
X-plore 6570:full respiratory protection mask made of robust and skin-friendly silicone.Code: DR111#19_2
Page 19
ESS II:fresh air system which protects vehicle occupants from the ingress of smoke or irritant gas.Code: DR111#29
Page 29
Dräger tubes:they make the concentration of around 500 different substances clearly visible.Code: DR111#32
Page 32
DrugTest 5000:saliva test which establishes current drug use with a high degree of probability.Code: DR111#36
Page 36
Multi-PID 2:photoionization detector for highly volatile organic compounds. Code: DR111#40
Page 40
XXS sensor:the smallest electrochemical sensor from Dräger – detects various gases and vapors.Code: DR111#54
Page 54
X-plore 8000:powered air-purifying respirator – purifies the ambient air intelligently and reliably.Code: DR111#56
Many customers were extensively surveyed before work began on the develop ment of a new powered air-purify ing respirator: X-plore 8000 supplies people working with various headpieces 1 with ambient air which has been purged of harmful particles, gases, and vapors. The air is drawn in through the inlet 2 facing away from the body via a silent blower unit 3 (hidden) and initially passes through a “labyrinth.” As a result, neither a sudden gush of water nor fl ying sparks are a threat to the intrinsic fi lter 4 (under the spray protection cover) in terms of protection ability. This could be a particle, gas, or combi nation fi lter depending on the application.
The internal readout of the color code signalizes to the respirator the kind of fi lter that has been fi tted and compensates for different initial resistance levels when dis-playing the particle fi lter saturation.
A lithium-ion battery 5 supplies power for several hours. Once it has been switched on, the electronics check all functions and informs the user of any faults. It recognizes the connected hose 6 by means of its RFID code and thus the type of headpiece being used (hood, helmet, protective visor, or mask) before setting the basic value for the volume fl ow rate, which can be adjusted manually. In addition, the system provides a clearly visible and audible signal and triggers a vibration alarm when a fi lter is reaching saturation point and needs replacing, as well as when no fi lter has been fi tted inadvertently. The respirator complies with the IP65 ingress protection rating, is protected against dust and jets of water from all directions, and is available with vari-ous carrying systems 7 – such as the design shown above, which can be decontaminated.
Fresh Air under the
Hood
47
6
1
2
3
5
X-plore 8000: the respirator filters the ambient air intelligently and reliably – tough and demanding jobs can be performed under various open and closed headpieces