Analytical X-ray Manual

Analytical X-ray Manual

TABLE OF CONTENTS

Chapter I - Overview of Safety Requirements for Analytical X-Ray Equipment

Chapter II - Radiation Safety Organization at ASU

Chapter III - Registration for Permits: Operator and Equipment

Chapter IV - Personnel Dosimetry

Chapter V - Radiation Control Measures for Analytical X-Ray Equipment

Appendix A: Radiation Hazards of Analytical X-Ray Equipment

Appendix B: NRC Regulatory Guide 8.29 Instruction Concerning Risk From Occupational Radiation Exposure

Appendix C: NRC Regulatory Guide 8.13 Instruction Concerning Prenatal Radiation Exposure

Appendix D: ARRA Form 6 Notice to Employees

Appendix E: RPE/Analytical X-ray Survey Form

Appendix F: RPE/Analytical X-ray Registration Form

Appendix G: ARTICLE 9. RADIATION SAFETY REQUIREMENTS FOR PARTICLE ACCELERATORS

Appendix H: Application for Radiation Producing Equipment License

Scope and Applicability

This manual applies to all personnel working at or visiting ASU who procure or utilize analytical x-ray equipment. The Arizona Radiation Regulatory Agency defines analytical x-ray equipment as any device which utilizes x-rays for examining the structure and/or composition of materials. This includes x-ray diffraction and x-ray fluorescence analysis equipment.

ASU procures and uses analytical x-ray equipment under regulations issued by the Arizona Radiation Regulatory Agency (ARRA). Use of this equipment at ASU is subject to inspection and review by personnel from ARRA. In order to ensure compliance with Arizona regulations for the control of ionizing radiation, it is essential that personnel understand and follow provisions of this manual.

Chapter I - Overview of Safety Requirements for Analytical X-Ray Equipment

1.1 Application for RPE Licence & Equipment Registration

Registrants must obtain approval for obtaining RPE equipment by using the form "Application for Radiation Producing Equipment Licence" (Appendix H). Analytical x-ray equipment must be registered with the Office of Radiation Safety. The registrant must be a full time faculty, academic professional, or staff member at ASU who bears overall responsibility for safe use of registered equipment. New equipment must be registered prior to operation. The ASU code for ordering new x-ray or radiation producing equipment is 781092 Radiation Producing Equipment (x-ray).

1.2 Training

All individuals operating analytical x-ray equipment must obtain training on the hazards associated with the equipment and proper safety control measures.

1.3 Safety Control Measures

Analytical x-ray equipment must be operated under administrative and/or engineering control measures approved by the Radiation Safety Committee or Radiation Safety Officer. These measures include written procedures for operation and alignment, periodic testing of interlocks and safety devices, proper labeling of equipment and posting of rooms, and limits on radiation fields produced by the equipment.

1.4 Safety Surveys

Periodic safety surveys of analytical x-ray equipment will be conducted by Office of Radiation Safety staff.

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Chapter II - Radiation Safety Organization at ASU

2.1 Arizona Radiation Regulatory Agency Arizona State University procures and uses analytical x-ray equipment under regulations of the Arizona Radiation Regulatory Agency (ARRA). The regulations require that ASU personnel use ARRA approved procedures for the control of all analytical x-ray equipment. ARRA also requires that analytical x-ray equipment be registered with that agency.

ASU is subject to inspection by ARRA. If ARRA finds that ASU is not in compliance with state regulations, they may issue fines, or in the case of serious infractions, suspend or revoke analytical x-ray equipment use.

ARRA Rules and Regulations, and supporting documentation are on file in the Office of Radiation Safety for review by ASU personnel.

2.2 Radiation Safety Committee ASU governs the use of analytical x-ray equipment through the Radiation Safety Committee. This committee is a group of professionals appointed by the president of ASU to establish policy and regulations for the use of radiation sources and to oversee all aspects of radiation safety. The committee meets at least quarterly to review the university's radiation safety program.

2.3 Radiation Safety Officer The Radiation Safety Officer is responsible for implementing the radiation safety program as directed by the RSC. He is assisted by the staff of the Office of Radiation Safety.

Specific duties of the Radiation Safety Officer and his staff include:

a. Furnishing consulting services on all aspects of radiation safety and protection.

b. Conducting surveys and making hazard evaluations for analytical x-ray equipment.

c. Assuring that the prescribed control measures are in effect, recommending or approving substitute or alternate control measures when the primary ones are not feasible or practical, and periodically auditing the status of those control measures in use.

d. Approving standard operating procedures, alignment procedures, and other procedures that may be part of the requirements for administrative and procedural control measures.

e. Distributing and processing personnel monitoring devices, and maintaining personnel exposure records.

f. Insuring that personnel are properly instructed in the appropriate procedures for using analytical x-ray equipment.

g. Maintaining a current inventory of all analytical x-ray equipment at ASU.

The Radiation Safety Officer has the authority to restrict or terminate use of radiation producing equipment in cases where use is felt to be in violation of regulations or otherwise represents a radiological hazard. Such actions are reviewed by the Radiation Safety Committee.

2.4 Registration

All analytical x-ray equipment at ASU must be registered with the Office of Radiation Safety, which in turn registers these devices with ARRA (Appendix H). All analytical x-ray equipment must be registered to a faculty, academic professional, or staff member of ASU who maintains responsibility for all aspects of safety for the registered equipment. Specific responsibilities of the registrant include:

h. Registration of new equipment with the Office of Radiation Safety within 30 days of receipt and prior to operation.

i. Ensuring that operators are properly trained with respect to safe operation, and made aware of hazards associated with the equipment.

2.5 Operators and License Holders Individuals who operate analytical x-ray equipment must obtain training from the Radiation Safety Officer prior to use of the equipment. They must also obtain instruction from the registrant on the operating procedures for the equipment.

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Chapter III - Registration for Permits: Operator and Equipment

3.1 Registration of Analytical X-Ray Equipment All analytical x-ray equipment at ASU must be registered with the Office of Radiation Safety. Registrants must be full time faculty, academic professional, or staff of ASU.

Analytical x-ray equipment is registered by submitting the appropriate form to the Radiation Safety Officer. Registration forms are available in the Office of Radiation Safety. Registration forms must be submitted within 30 days of receipt and prior to operation of the equipment. The commodity code for purchasing new x-ray or radiation producing equipment is 781092 Radiation Producing Equipment (x-ray etc.).

3.2 Training Required for Operators Operators must receive training in the following topics:

a. Types and amounts of radiation to which workers could be exposed;

b. Health effects of exposure to low doses of ionizing radiation; c. Precautions and procedures to minimize exposure to ionizing

radiation; d. Applicable provisions of ARRA Rules and Regulations, and rules

and regulations established by ASU;

e. Responsibilities of personnel using radiation producing equipment including the need to bring violations of ARRA and ASU Rules and Regulations to the attention of the Radiation Safety Officer;

f. Response in the event of exposures to radiation and other emergencies;

g. Rights of workers to have access to radiation exposure records. h. Correct procedures for safe and effective operation of the

analytical x-ray equipment.

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Chapter IV - Personnel Dosimetry

4.1 TLD Badges TLD badges are used at ASU to monitor personnel for exposure of the body to penetrating ionizing radiation such as gamma and x-rays, and exposure of the skin to less penetrating radiation such as beta particles. For most individuals, results of the TLD badge readings are also used as estimates for the exposure of the lens of the eye. TLD badges are required for operators of most analytical x-ray equipment at ASU. They are not required for some cabinet type equipment. The need for TLD badges is determined by the Radiation Safety Officer at the time of the initial radiation safety training.

TLD badges must be worn on the trunk of the body at or above the waist. Dosimetry devices must not be taken home or left in laboratory areas where they may be exposed to radiation or excessive heat. The badge is sensitive to heat and humidity.

4.2 Extremity Dosimetry Ring dosimetry devices are used at ASU to monitor for radiation exposure to the hands are issued to most personnel using analytical x-ray equipment. Ring badges must be worn with the sensitive portion of the ring towards the source.

4.3 Dosimeter Exchange The TLD badges and the rings are exchanged on a quarterly basis. ORS personnel hand carry TLDs and rings to department offices during the last few days of each quarter. Old TLDs and rings must be hand carried to the ORS. Campus mail must not be used. This policy has been established to avoid exposure of TLDs and rings to sources of radiation, heat, and humidity during transit and maintain the chain of custody.

Dosimetry should be returned to the ORS during the first 5 working days of the new quarter.

4.4 Lost or Damaged Dosimeters Periodically, dosimetry devices are lost or damaged. This should be reported to ORS staff immediately so that replacement dosimeters can be issued.

4.5 Regulatory Dose Limits

4.5.1 Limits for Radiation Workers

ARRA has imposed limits on the dose of ionizing radiation which may be received by individuals working with sources of ionizing radiation. These limits are shown in Table 4-1.

Annual Limit, which is the more limiting of:

1. Total Effective Dose Equivalent 2. Sum of the deep dose equivalent and committed dose

equivalent to any organ or tissue other than the lens of the eye

Annual Limit, which is the more limiting of:

a. Total Effective Dose Equivalent

b. Sum of the deep dose equivalent and committed dose equivalent to any organ or tissue other than the lens of the eye

5 rem (0.05 Sv)

50 rem (0.5 Sv)

Eye Dose Equivalent 15 rem (0.15 Sv)

Shallow Dose Equivalent to the skin or to each of the extremities

50 rem (0.5 Sv)

Table 4-1 Regulatory Dose Limits

4.5.2 Limits to the Embryo-Fetus of Declared Pregnant Workers

Due to concerns about prenatal radiation exposure (See Appendix C) ARRA regulations provide separate limits for the embryo/fetus of Declared Pregnant Workers. The limit is 0.5 rem dose equivalent to the fetus during pregnancy.

This limit applies only for workers who have formally declared pregnancy in writing. Declaration of pregnancy should be sent to the Radiation Safety Officer and include the estimated date of conception.

Individuals concerned about radiation and pregnancy should feel free to speak to the Radiation Safety Officer.

4.5.3. Limits for Members of the Public

The regulatory limit for members of the public is 0.1 rem total effective dose equivalent per year. This limit applies to all individuals who are not trained to work with sources of ionizing radiation. At ASU this includes most faculty, staff and students.

4.6 ALARA In view of uncertainties that exist concerning the health effects of exposure to low doses of Radiation (see Appendix A), it is prudent to keep doses to personnel "as low as is reasonably achievable" (ALARA). Each user of radiation sources at ASU has the responsibility to incorporate shielding and protective devices, and to take any other steps required to keep doses ALARA.

4.7 Investigation Levels In order to maintain doses ALARA, investigational levels have been established at ASU. These dose levels are shown in Table 4-2. The limits are evaluated on a quarterly basis.

Personnel exposures equal to or greater than Investigational Level I, are reviewed by the RSO, who reports the results to the RSC at their next regularly scheduled meeting. The RSC may require corrective actions on the part of the RSO or registrant.

Personnel exposures equal to or exceeding Investigational Level II are investigated in a timely manner by the RSO who takes immediate action if warranted. A report of the investigation, actions taken, and a copy of the individual's radiation dosimetry history are presented to the RSC at their regularly scheduled meeting following completion of the investigation. The RSC may impose restrictions on the user as warranted.

Investigational limits exceeding those listed in Table 4-2 may be established by the RSC for a worker or group of workers when the higher investigational levels are consistent with good ALARA practice for the work being conducted by the individual or group.

Limit Level (rem/quarter)

Level I Level II Total Effective Dose Equivalent 0.065 0.200 Eye Dose Equivalent 0.180 0.600 Shallow Dose Equivalent to the Skin or to each of the Extremities 0.625 2.000

Table 4-2 Investigational Dose Levels

4.8 Reports to Workers on Radiation Dosimetry The ORS keeps careful records on results of radiation dosimetry for personnel on the ASU dosimetry program. These records are available for review by these personnel.

4.8.1 Review of Records in the ORS

Personnel issued dosimeter devices are welcome to review dosimetry results on file in the ORS. This review should be arranged with the ORS. The RSO requires positive identification of individuals seeking access to dosimetry results since these records are covered by state and federal privacy laws.

4.8.2 Annual Dosimetry Report

During the spring of each year, a report on dosimetry results for the previous calendar year is sent to each individual issued dosimeters at ASU. A summary of individual dosimetry results are also sent to the registrant responsible for supervising the work requiring dosimetry.

4.8.3 Notification of Results Exceeding Investigation Limits

Personnel are notified quickly of results which exceed Investigation Levels listed in Table 4-2. Personnel are not notified quarterly of routine dosimetry results which do not exceed the Investigation Levels.

4.9 Radiation Dosimetry Units The following paragraphs explain the dosimetry units used in this chapter.

4.9.1 Absorbed Dose

The amount of energy absorbed by irradiated tissue is an important variable in the assessment of radiation risk and damage. The absorbed dose is defined as the energy absorbed per unit mass of tissue. The traditional unit for absorbed dose is the rad.

1 rad = 100 erg / gram

The rad is being replaced by a new unit based on the International System of Units (SI). The new unit is the Gray.

1 Gray = 1 joule / kg

Spending a little time with the units will reveal that

1 Gray = 100 rad

The SI units have not found widespread use in radiation protection in this country. It is the system of units which is used internationally, however, and will eventually replace the older units here.

4.9.2 Dose Equivalent

Alpha, beta, gamma/x-radiation, and neutrons differ in the damage produced for a given absorbed dose. Special units of dose equivalent are used to adjust the absorbed dose for this difference. The traditional unit of dose equivalent is the rem.

1 rem = 1 rad x Q

Q is called the quality factor and is assigned to radiation based on the relative risk for a given dose. Currently, a quality factor of 1 is used for photons, electrons, and positrons. A quality factor of from 2.3 to 10 is used for neutrons, depending on their energy, and a quality factor of 20 is used for alpha particles. The SI unit for dose equivalent is the Sievert.

1 Sievert = 1 Gray x Q

RADIATION TYPE Q

x and gamma rays 1

beta particles 1

alpha particles 20

neutrons 2.3 to 10

Table 4-3 Radiation Quality Factors

4.9.3 Exposure

The energy absorbed by irradiated tissue is rarely measured directly. Most radiation detection instrumentation used in radiation protection measures the number of ion pairs produced in a volume of gas. The traditional unit used to measure ionization in air is the roentgen:

1 Roentgen = 2.58 x 104 coulombs / kg air

The roentgen is defined only for x-rays and gamma rays. It is not used for beta, alpha, or neutron radiation.

Exposure of 1 roentgen of radiation results in an absorbed dose to tissue of 0.97 rad. For purposes of radiation protection and dosimetry, it is usually assumed that the roentgen, rad, and rem are numerically equivalent for gamma rays and x-rays.

4.9.4 Effective Dose Equivalent

The various organs and tissues in the body differ in their sensitivity to radiation. The bone marrow and other blood forming tissues of the body are much more sensitive to radiation than the skin. In order to quantify the risk from radiation exposure when the body is not irradiated uniformly (different doses are delivered to different organs or tissues) a unit called the effective dose equivalent has been developed. The effective dose equivalent is given the symbol H and is defined as:

Where DI is the dose equivalent received by the ith tissue or organ, and WI is a weighting factor which is assigned to the ith tissue or organ depending on its sensitivity to radiation. Weighting factors currently in use are listed in the accompanying table. The units of the effective dose equivalent are the rem and the Sievert depending on which is used for the individual tissue or organ dose equivalent.

TISSUE WEIGHTING FACTOR

Gonads 0.25

Breast 0.15 Red Bone Marrow 0.12 Lung 0.12 Thyroid 0.03 Bone Surfaces 0.03 Remainder 0.30 Whole Body 1.00 The 0.30 for remainder results from 0.06 for each of 5 remaining organs, excluding the skin and the lens of the eye, that receive the highest doses.

Table 4-4 Effective Dose Equivalent Weighting Factors

4.9.5 Committed Effective Dose Equivalent

When radioactive materials are inhaled, ingested, or otherwise internalized, they may be retained in some tissues for a long period of time. In some cases a fraction of the material may remain in the body for years. The committed effective dose equivalent is the effective dose equivalent that will be received from an intake of radioactive material by an individual during the 50 year period following the intake.

4.9.6 Deep Dose Equivalent

The deep dose equivalent is the dose equivalent at a tissue depth of 1 cm.

4.9.7 Shallow Dose Equivalent

The shallow dose equivalent is the dose equivalent at a tissue depth of 0.0007 cm averaged over an area of 1 square centimeter.

4.9.8 Eye Dose Equivalent

The eye dose equivalent is the dose equivalent to the lens of the eye.

4.9.9 Total Effective Dose Equivalent

The total effective dose equivalent is the sum of the committed effective dose equivalent for all intakes of radioactive material and the deep dose equivalent to the whole body resulting from exposure to external sources of radiation.

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Chapter V - Radiation Control Measures for Analytical X-Ray Equipment

5.1 Administrative Requirements for Use of Analytical X-Ray Equipment

5.1.1. Registration

Analytical x-ray equipment at ASU must be registered to a single member of the faculty, academic professional, or staff who bears responsibility for safe use of the equipment by all other individuals. See Appendix F.

5.1.2. Notification of Receipt of Equipment

The Office of Radiation Safety be notified within 30 working days of the receipt of analytical x-ray equipment.

5.1.3. Radiation Surveys of Equipment

After initial installation, and upon completion of alterations or maintenance, the Office of Radiation Safety must conduct a survey for radiation leakage before the unit may be placed in service. Surveys may be scheduled through the Office of Radiation Safety. See Appendix E.

5.1.4. Maintenance

Only properly trained maintenance personnel may install, repair, or make other than routine modifications to the x-ray generating apparatus and the tube housing apparatus complex.

5.1.5 Testing of Safety Devices

Safety interlocks and other safety devices will be tested monthly by registrants. Records of these tests should be maintained by the registrant for review by Office of Radiation Safety or ARRA personnel.

5.1.6. Emergency Procedures

Written emergency procedures pertaining to radiation safety shall be established for each x-ray producing apparatus by the Radiation Safety Officer and posted in a conspicuous location. These procedures list the telephone number(s) of the Radiation Safety Officer and include the following actions to be taken in case of a known, or suspected accident involving radiation exposure:

a. Notify the Radiation Safety Officer, and b. Arrange for medical examination.

5.1.7. Unattended Use of Equipment

Analytical x-ray equipment must not be left unattended while the tube is energized unless:

c. An interlock device is provided to prevent accidental entry into the primary beam, and

d. The stray radiation at any accessible point at a distance of 10 inches from the tube housing containnment, as measured with monitoring instrument appropriate for the energy range generated, is no greater than 2mR per hour.

5.2 Equipment Requirements

5.2.1. Labeling

All analytical x-ray equipment must be labeled with a readily discernible sign or signs bearing the radiation symbol and the words:

e. "CAUTION - HIGH INTENSITY X-RAY BEAM", or words having a similar intent, on the x-ray source housing; and

f. "CAUTION - RADIATION - THIS EQUIPMENT PRODUCES RADIATION WHEN ENERGIZED", or words having similar intent, near any switch that energizes an x-ray tube.

5.2.2. Visual Indicators

g. The primary on-off switch for each tube must include a visual indication of the tube status, in the form of a warning light on the control console and a warning light on the tube housing, wired so that the x-ray tube cannot be energized if the warning light fails. Such lights must operate at all times when the tube is energized and must light at no other times.

h. A shutter status (open or closed) indication must be provided in the area adjacent to the tube head so that the position of the shutter is readily discernible.

5.2.3. Interlocks

i. An interlock device which prevents entry of limbs, fingers, hands, wrists, etc., into the primary beam or causes the primary beam to be shut off, must be utilized, unless otherwise approved by the Radiation Safety Committee.

j. It must not be possible to resume operation without resetting the beam "ON" switch at the control panel.

5.2.4. Beam Shutters

On open-beam configurations, each port on the radiation source housing must be equipped with a shutter that cannot be opened unless a collimator or a coupling has been connected to the port.

5.3. Facility Requirements

5.3.1. Dedicated Work Space

k. X-ray diffraction and spectrographic equipment must be placed in a room separate from other work area, unless otherwise approved by the Radiation Safety Committee.

l. Access to rooms containing analytical x-ray equipment must be secured to prevent unauthorized use of equipment.

m. All installations must display warning signs on the outside of all entrances to the room. Warning signs will be supplied and posted by the Office of Radiation Safety staff.

5.4. Radiation Limits

5.4.1. General

The local components of an analytical x-ray system must be located and arranged, and must include sufficient shielding or access control such that no radiation levels in excess of 80 mR per hour will exist in areas accessible to the fingers, hands, or forearms, or in excess of 5 mR per hour will exist in areas accessible to the whole body, lens of the eyes, blood forming organs, or gonads. When analytical x-ray

equipment is placed in a room utilized by personnel other than operators of the x-ray producing equipment, the limits for these radiation levels will be reduced by a factor of twenty.

5.4.2. Other Radiation Limits

n. Each x-ray tube housing must be so constructed that with all shutters closed the leakage radiation measured at a distance of 5 cm from its surface is not capable of producing a dose in excess of 2.5 mrem in one hour at any specified tube rating.

o. Each x-ray generator must be supplied with a protective cabinet which limits leakage radiation measured at a distance of 5 cm from its surface such that it is not capable of producing a dose in excess of 0.25 mrem in one hour.

p. Any apparatus utilized in beam alignment procedures must be designed in such a way that excessive radiation will not strike the operator. Particular attention should be given to viewing devices, in order to ascertain that lenses and other transparent components attenuate the beam to an acceptable level.

5.5 Requirements of Users 5.5.1. Training and Other Responsibilities

No individual will be permitted to act as an operator of a particular instrument until such individual has received an acceptable amount of training in the correct use of specific equipment and in radiation safety and is approved by the Radiation Safety Officer. Operators are responsible for:

q. Keeping radiation exposure to themselves and others as low as is practical.

r. Being familiar with safety procedures as they apply to each instrument.

s. Wearing of personnel monitoring devices, if required.

t. Notifying the Radiation Safety Officer of known or sususpected excessive radiation exposures.

5.5.2. Bypassing or Altering Interlocks and Safety Devices

If, for any reason, it is necessary to temporarily intentionally alter safety devices, such as bypassing interlocks or removing a shield, such action shall be:

u. Specified in writing and posted near the x-ray tube housing so that other persons will know the existing status of the machine.

v. Terminated as soon as possible.

5.5.3. Other

w. Personnel must not expose any part of their body to the primary beam.

x. Unused tube head ports must be secured in the closed position. These must be checked prior use when the machine has been left unattended.

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Appendix A: Radiation Hazards of Analytical X-Ray Equipment

Introduction

Analytical x-ray equipment makes use of very narrow collimated x-ray beams of high intensity. Exposure of the eyes or the skin of the body to the primary x-ray beam may result in severe radiation burns in a matter of seconds. These burns heal poorly, and on rare occasions have required amputation of fingers.

o Localized radiation burns produced by the high intensity primary x-ray beam is the principal hazard associated with the use of analytical x-ray equipment.

Scattered Radiation

A hazard may also exist from exposure to scattered radiation. Scattered radiation is produced when the primary beam strikes collimators, samples, beam stops or shielding. The intensity of the scattered radiation is a couple of orders of magnitude less than that of the primary beam. It is possible for these scattered radiation fields to result in exposures, which exceed regulatory limits, however.

o Scattered Radiation may exceed regulatory exposure limits.

Hazards Associated with X-Ray Exposure

The hazards most often associated with exposure to x-ray radiation include increased risk of cancer and increased risk of genetic effects in exposed populations. These effects are effectively discussed in a number of readily available publications and will not be elaborated upon in this document. NRC Regulatory Guides 8.29, entitled Instruction Concerning Risks from Occupational Radiation Exposure, and 3.13, entitled Instruction Concerning Prenatal Radiation Exposure published by the Nuclear Regulatory Commission have been included as Appendix B and C in this manual.

Skin Burns

As discussed in the introduction, the principal hazard associated with use of analytical x-ray equipment is localized skin burns following exposure to the primary beam.

o Experience with exposure of relatively large areas of skin to radiation has shown that it requires doses of approximately 300 rad (3 gray) to produce a visible reddening of the skin.

o Doses of approximately 1500 rad (15 gray) are required in order to produce serious burns with blistering.

o When doses reach 3000 rad (30 gray) very serious burns requiring skin grafts or amputation may result.

The bum symptoms may require from one to several weeks to develop, depending on the dose.

Burns Produced by X-Rays

Description of Tissue Damage Approximate Dose Required (gray)

Perceptible reddening of skin 3 Dry desquamation of skin 10 Wet desquamation and blistering 15 Ulceration and necrosis of skin 30

Target Size

Experiments have shown that when the irradiated area is very small, it takes higher doses to damage the skin.

o Decreasing the size of the irradiated area from 100 cm2 to 1 cm2 has been reported to require 10 times the dose to produce the same degree of damage.

o Further reduction of the irradiated area from 1 cm2 to 1 mm2 will again require 10 times the dose to produce the same damage.

Eye Damage

There have occasionally been reports of accidental exposure of the eye during use of analytical x-ray equipment. Doses capable of causing skin burns are capable of producing serious permanent damage to the eye.

o Studies have also shown that doses greater than 200 rad (2 gray) are capable of producing cataracts in the lens of the eye.

Intensity of the Primary X-Ray Beam

X-ray fields near a bare x-ray tube are very intense.

o For this reason, regulations do not allow the use of instruments without a protective tube housing or shield.

The x-ray tube housing contains one or more ports which provide a narrow beam of useful x-rays. The x-ray dose rate at the beam port may be several thousand rad per second (several tens of gray per second). Inadvertent placement of fingers at the beam port for even a second can result in serious burns.

As a further precaution, current regulations require a shutter for all beam ports on the tube housing. The shutters must automatically close unless a collimator, camera, or other equipment is attached to the beam port. Use of a beam collimator greatly increases safety of analytical x-ray equipment on two ways.

The dose rate at the hand of 10 cm collimator is reduced to several thousand rad per minute (several tens of gray per minute).

In addition, the dimensions of the collimated beam are usually on the order of 1 mm2.

The possibility of receiving a high dose to any portion of the skins is unlikely under these conditions. Natural movement of the hand will ensure that the same 1 mm2 area of the skin is not irradiated for any significant amount of time.

The intensity of the x-ray beam decreases very rapidly as the distance from the tube increases. The dose rate as a function of the distance from the tube follows the well known inverse square relationship.

Possible Radiation Intensity Near Analytical X-Ray Equipment

Location Dose Rate Primary beam at tube port several tens of gray per second

Primary beam at end of 10 cm collimator several tens of gray per minute

Scattered radiation near sample several milligray per hour Scattered radiation near table edge 1 milligray per hour

Scattered Radiation

Radiation is scattered when the primary beam impinges on surfaces of collimators, samples, beam stops, or shielding. The intensity of the scattered radiation may be as high as several hundred millirad per hour (several milligray per hour) near the collimator, but rarely exceeds 100 millirad (1 milligray) per hour at the edge of the equipment table.

Additional Protective Devices on Analytical X-Ray Equipment

The information provided above on the x-ray fields produced during use of analytical x-ray equipment represents a worst case type of configuration, Most equipment is not used in an open beam configuration. Usually a combination of filters, cameras, beam enclosures and shielding are used and reduce the radiation fields around the equipment significantly.

X-rays produced in analytical x-ray equipment are usually filtered to modify the quality of the beam. These filters may be placed in front of the collimator, but are often placed in front of the sample or detectors. When the primary beam is filtered, the intensity of the beam is reduced to by a factor of from 2 to 6.

Often a camera or other equipment is used which encloses the beam. In these cases, the radiation hazard is limited to scattered radiation.

Fluorescence spectrometers utilize a special interlocked sample chamber, which encloses the beam. In this equipment the beam is more intense that that required for diffractometers. In addition, the sample must usually be closer to the beam port. In order to prevent access to the high radiation levels of the primary beam, fluorescence equipment must be equipped with an interlocked sample chamber. Access to the sample requires removal of an interlocked cover. Removal of the cover shuts off the power or blocks the beam thereby preventing injury to fingers, which are carelessly placed in the sample chamber.

In all but the oldest equipment, some type of enclosure is used which will prevent inadvertent insertion of hands and fingers into the path of the primary beam. These enclosures may be constructed of plastic or glass and are usually interlocked. When the enclosure is opened, the power is shut off, or the beam is blocked.

Shielding made of plastic, glass, or metal may also be used to reduce the level of scattered radiation in occupied areas. This type of shielding is not typically interlocked.

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Appendix B: NRC Regulatory Guide 8.29 Instruction Concerning Risk From Occupational Radiation Exposure

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Appendix C: NRC Regulatory Guide 8.13 Instruction Concerning Prenatal Radiation Exposure

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Appendix D: ARRA Form 6 Notice to Employees

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ARRA Form 6: Notice to Employees

MS Word Version ARRA Form 6: Notice to Employees

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Appendix E: RPE/Analytical X-ray Survey Form

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RPE/Analytical X-ray Survey Form

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RPE/Analytical X-ray Survey Form

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Appendix F: RPE/Analytical X-ray Registration Form

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RPE/Analytical X-ray Registration Form

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RPE/Analytical X-ray Registration Form

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Appendix G: ARTICLE 9. RADIATION SAFETY REQUIREMENTS FOR PARTICLE ACCELERATORS

R12-1-901. Purpose and Scope

A. This Article establishes procedures and requirements for the registration and the use of particle accelerators.

B. In addition to the requirements of this Article, all registrants are subject to the requirements of Articles 1, 2, 4, and 10. Registrants engaged in industrial radiographic operations are subject to the requirements of Article 5, and registrants engaged in the healing arts are subject to the requirements of Article 6 of these rules. Registrants engaged in the use or production of radioactive material are subject to the requirements of Article 3.

Historical Note

Former Rule Section I.1; Former Section R12-1-901 repealed, new Section R12-1-901 adopted effective June 30, 1977 (Supp. 77-3). Amended effective June 13, 1997 (Supp. 97-2). R12-1-902. Repealed

Historical Note

Former Rule Section I.2; Former Section R12-1-902 repealed, new Section R12-1-902 adopted effective June 30, 1977 (Supp. 77-3). Amended effective June 13, 1997 (Supp. 97-2). Section repealed by final rulemaking at 5 A.A.R.

1817, effective May 12, 1999 (Supp. 99-2). R12-1-903. General Requirements for the Issuance of a Registration for Particle Accelerators

C. The requirements in this section supplement the registration requirements in 12 A.A.C. 1, Article 2.

D. The Agency shall approve a registration application for use of a particle accelerator only if the Agency determines that:

1. The applicant is qualified by training and experience to use the accelerator for the purpose requested according to this Article, and Articles 4 and 10, of these rules to minimize danger to public health or property;

2. The applicant's proposed equipment, facilities, operating, and emergency procedures are adequate to protect health and minimize danger to public health and safety or property;

3. The issuance of the registration will not be inimical to the health and safety of the public, and the applicant satisfies any applicable special requirement in R12-1-904;

4. The applicant has appointed a radiation safety officer; 5. The applicant's staff has substantial experience in the use of

particle accelerators for the intended uses; and 6. The applicant has an adequate training program for particle

accelerator operators.

Historical Note

Former Rule Section I.3; Former Section R12-1-903 repealed, new Section R12-1-903 adopted effective June 30, 1977 (Supp. 77-3). Amended effective Aug. 8, 1986 (Supp. 86-4). Amended effective June 13, 1997 (Supp. 97-2). Amended by final rulemaking at 5 A.A.R. 1817, effective May 12, 1999 (Supp. 99-2). R12-1-904. Special Registration Requirements for Medical Use of Particle Accelerators

E. The requirements in this Section supplement the registration requirements in R12-1-903.

F. An applicant that is a "medical institution", as defined in 12 A.A.C. 1, Article 7, and performing human research shall appoint a radiation safety committee, meeting the requirements in R12-1-706.

G. The applicant shall ensure that an individual designated as an authorized user on the application is an Arizona licensed physician; approved by the radiation safety committee, if applicable; and is:

1. Certified in:

a. Radiology, therapeutic radiology, or radiation oncology by the American Board of Radiology; or

b. Radiation oncology by the American Osteopathic Board of Radiology; or

c. Radiology, with specialization in radiotherapy, as a British "Fellow of the Faculty of Radiology" or "Fellow of the Royal College of Radiology"; or

d. Therapeutic radiology by the Canadian Royal College of Physicians and Surgeons; or

2. Engaged in the active practice of therapeutic radiology, and has completed 200 hours of instruction in basic techniques applicable to the use of a particle accelerator, 500 hours of supervised work experience, and a minimum of 3 years of supervised clinical experience.

a. To satisfy the requirement for instruction, the classroom and laboratory training shall include all of the following subjects.

i. Radiation physics and instrumentation; ii. Radiation protection; iii. Mathematics pertaining to the use and

measurement of radiotherapy; and iv. Radiation biology.

b. To satisfy the requirement for supervised work

experience, training shall occur under the supervision of an authorized user at a medical institution and shall include:

i. Reviewing full calibration measurements and periodic spot checks;

ii. Preparing treatment plans and calculating treatment times;

iii. Using administrative controls to prevent misadministration;

iv. Implementing emergency procedures to be followed in the event of the abnormal operation of a particle accelerator; and

v. Checking and using survey meters.

c. To satisfy the requirement for a period of supervised clinical experience, training shall include 1 year in a formal training program approved by the Residency Review Committee for Radiology of the Accreditation Council for Graduate Medical Education or the Committee on Postdoctoral Training of the American Osteopathic Association and an additional 2 years of clinical experience in therapeutic radiology under the supervision of an authorized user at a medical institution. The supervised clinical experience shall include:

i. Examining individuals and reviewing their case histories to determine their suitability for

treatment, noting any limitations or contraindications;

ii. Selecting the proper dose and how it is to be administered;

iii. Calculating the therapy doses and collaborating with the authorized user in the review of patients' or human research subjects' progress and consideration of the need to modify originally prescribed doses, as warranted by patients' or human research subjects' reaction to radiation; and

iv. Post-administration follow up and review of case histories.

d. Therapeutic radiology by the Canadian Royal College of Physicians and Surgeons; or

H. With the application the applicant shall provide the name of each authorized user, and the training and experience that satisfies the requirements in subsection (C).

I. Each licensee shall establish and maintain a written quality management program to provide high confidence the radiation produced by the particle accelerator will be administered as directed by an authorized user. The quality management program shall include written policies and procedures to meet the specific patient safety objectives established by the Radiation Safety Officer or Radiation Safety Committee, if applicable.

J. Each particle accelerator shall be calibrated by an expert meeting the training and experience qualifications in R12-1-716(G).

K. The Agency shall inspect a particle accelerator before it is used to treat a human.

Historical Note

Former Rule Section I.4; Former Section R12-1-904 repealed, new Section R12-1-904 adopted effective June 30, 1977 (Supp. 77-3). Amended effective Aug. 8, 1986 (Supp. 86-4). Amended by final rulemaking at 5 A.A.R. 1817, effective May 12, 1999 (Supp. 99-2). R12-1-905. Repealed

Historical Note

Adopted effective June 30, 1977 (Supp. 77-3). Repealed effective August 8, 1986 (Supp. 86-4). R12-1-906. Limitations

L. No registrant shall permit any person to act as a particle accelerator operator until such person:

1. Has been instructed in radiation safety and shall have demonstrated an understanding thereof;

2. Has received copies of and instruction in this Article and the applicable requirements of Articles 4 and 10, pertinent registration conditions and the registrant's operating and emergency procedures, and shall have demonstrated understanding thereof; and

3. Has demonstrated competence to use the particle accelerator, related equipment, and survey instruments which will be employed in his assignment.

M. Both the Radiation Safety Committee and the Radiation Safety Officer shall have the authority to terminate the operations at a particle accelerator facility if such action is deemed necessary to protect health and/or minimize danger to public health and safety or property.

Historical Note

Adopted effective June 30, 1977 (Supp. 77-3). R12-1-907. Shielding and Safety Design Requirements

N. A person experienced in the principles of radiation protection and installation design shall be consulted in the design of a particle accelerator installation and called upon to perform a radiation survey when the accelerator is 1st capable of producing radiation.

O. The registrant shall provide each particle accelerator installation with the primary and secondary barriers that are necessary to assure compliance with R12-1-408 and R12-1-416.

Historical Note

Adopted effective June 30, 1977 (Supp. 77-3). Amended subsection (A) effective Aug. 8, 1986 (Supp. 86-4). Amended effective June 13, 1997 (Supp. 97-2). R12-1-908. Particle accelerator controls and interlock systems

P. Instrumentation, readouts and controls on the particle accelerator control console shall be clearly identified and easily discernible.

Q. All entrances into a target room or other high radiation area shall be provided with interlocks that shut down the machine under conditions of barrier penetration.

R. When an interlock system has been tripped, it shall only be possible to resume operation of the accelerator by manually resetting controls at the position where the interlock has been tripped, and lastly at the main control console.

S. Each safety interlock shall be on a circuit which shall allow its operation independently of all other safety interlocks.

T. All safety interlocks shall be fail safe, i.e., designed so that any defect or component failure in the interlock system prevents operation of the

accelerator.

U. A scram button or other emergency power cutoff switch shall be located and easily identifiable in all high radiation areas. Such a cutoff switch shall include a manual reset so that the accelerator cannot be restarted from the accelerator control console without resetting the cutoff switch.

Historical Note

Adopted effective June 30, 1977 (Supp. 77-3). R12-1-909. Warning Devices

V. All areas, except those in medical facilities, designated as high radiation areas, and entrances to the areas shall be equipped with easily observable flashing or rotating warning light system that operates when, and only when, radiation is being produced. Medical facilities shall be equipped with a continuously operating warning light system.

W. Except in facilities designed for human exposure, each high radiation area shall have an audible warning device which shall be activated for 15 seconds prior to the creation of the high radiation area. The warning device shall be clearly discernible in all high radiation areas and all radiation areas.

X. Barriers, temporary or otherwise, and pathways leading to high radiation areas shall be identified in accordance with R12-1-428 and R12-1-429.

Historical Note Adopted effective June 30, 1977 (Supp. 77-3). Amended effective June 13, 1997 (Supp. 97-2). R12-1-910. Operating procedures

Y. Particle accelerators, when not in operation, shall be secured to prevent unauthorized use.

Z. Only a switch on the accelerator control console shall be routinely used to turn the accelerator beam on and off. The safety interlock system shall not be used to turn off the accelerator beam except in an emergency.

AA. All safety and warning devices, including interlocks, shall be checked for proper operability at intervals not to exceed 3 months. Results of such tests shall be maintained for inspection at the accelerator facility.

BB. Electrical circuit diagrams of the accelerator, and the associated interlock systems, shall be kept current and maintained for inspection by the Agency and available to the operator at each accelerator facility.

CC. If, for any reason, it is necessary to intentionally bypass a safety interlock or interlocks, such action shall be:

1. Authorized in writing by the Radiation Safety Committee and/or Radiation Safety Officer;

2. Recorded in a permanent log and a notice posted at the interlock(s) so bypassed and at the accelerator control console; and

3. Terminated as soon as possible. DD. A copy of the current operating and emergency procedures

shall be maintained at the accelerator control panel.

Historical Note

Adopted effective June 30, 1977 (Supp. 77-3). Amended subsection (D) effective Aug. 8, 1986 (Supp. 86-4). R12-1-911. Radiation Survey Requirements

EE. The registrant shall ensure that a portable survey instrument is available at all times in a particle accelerator facility.

FF. A person experienced in the principles of radiation protection and installation design shall:

1. Check operation of the portable survey instrument using a known radiation source prior to its use;

2. Perform and document a radiation protection survey when changes have been made in shielding, operation, equipment, or occupancy of adjacent areas;

3. Perform surveys to determine the amount of airborne particulate radioactivity present in areas of airborne hazards in particle accelerator facilities of greater than 30 Mev;

4. Perform periodic smear surveys to determine the degree of contamination in target and adjoining areas when the conditions described in subsection (B)(3) exist;

5. Perform surveys as prescribed in the written procedures established by the Radiation Safety Officer of the particle accelerator facility.

GG. The registrant shall retain the following records: 1. Records of any radiation protection survey required in

subsection (B), and an associated facility description, required in R12-1-202(E), until the registration is terminated.

2. Records of particle accelerator calibration, spot checks, personnel radiation safety system tests, and periodic radiation protection surveys until the registration is terminated.

Historical Note

Adopted effective June 30, 1977 (Supp. 77-3). Amended effective Aug. 8, 1986 (Supp. 86-4). Amended by final rulemaking at 5 A.A.R. 1817, effective May 12, 1999 (Supp. 99-2). R12-1-912. Ventilation Systems

HH. A registrant or licensee shall provide the means to ensure that personnel entering any area where airborne radioactivity may be produced will not be exposed to airborne radioactive material in excess of those limits specified in Article 4, Appendix B, Table II of this Chapter.

II. A registrant or licensee shall not vent, release, or otherwise discharge airborne radioactive material to an uncontrolled area which exceed the limits specified in Article 4, Appendix B, Table II of this Chapter, except as authorized pursuant to R12-1-435. For purposes of this Section, concentrations may be averaged over a period not greater

than 1 year. Every reasonable effort should be made to maintain releases of radioactive material to uncontrolled areas as far below the limits in Appendix B, Table II of this Chapter, as practicable.

Historical Note

Adopted effective June 30, 1977 (Supp. 77-3). Amended effective Aug. 8, 1986 (Supp. 86-4). Amended effective June 13, 1997 (Supp. 97-2).

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Appendix H: Application for Radiation Producing Equipment License

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