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SECTION 10:
Laboratory Procedures for Radioisotopes
Radioisotope Inventory (top)
In each laboratory a Radioisotope Inventory Log shall be maintained,
containing an inventory of radioisotopes, noting the element, its mass
number, date received, amount received, dates of withdrawal for use
and amount withdrawn, date of disposal of waste, manner of disposal,
and estimated amount of waste. In short, a continual record must be
maintained from receipt to disposal or decay.
The maintenance of an inventory of target activity levels for the targets
which are routinely activated and investigated at the Jadwin Cyclotron
is difficult because of the broad spectrum of activities and activity
levels met in these targets. However, it is possible to estimate activity
levels or to express the data in mr/hour at some specified distance.
It is necessary that a record be kept indicating the disposition of
these materials.
Reports (top)
Two monthly reports must be filed by the "Authorized
User"
with the Office of Environmental Health and Safety: an inventory of
radioisotopes on hand (including all wastes not yet removed from the
University) and a summary of radioisotope disposals. The Office of Environmental
Health and Safety collects and collates the inventory data from all
"Authorized Users." The "Authorized User's" inventory
report (using EHS-HP Form #201) is filed with the Office of Environmental
Health and Safety each month and identifies all radioactive material
on hand, including wastes. The forms for these reports are available
from the Office of Environmental Health and Safety.
Survey Equipment (top)
1. A person using open or "Sealed Sources," opening packages
containing radioisotopes, or performing physical or chemical manipulation
of radioisotopes must have immediately available a suitable, operative
radiation detector. This detector must be able to indicate either dose
rate or activity as may be proper considering the nature and activity
of the source.
2. All portable radiation survey meters must be registered with the
Office of Environmental Health and Safety in order for calibration services
to be provided and calibration and repair records to be maintained.
Any "Authorized User" who purchases a new survey meter or
otherwise obtains a survey meter not previously registered must promptly
notify the Office of Environmental Health and Safety.
3. Each portable radiation survey meter must have a radioactive check
source affixed to it or otherwise provided with it. Check sources are
available from the Office of Environmental Health and Safety. The check
source is provided to enable the "User" to determine whether
a survey meter is operating properly. Each "User" must performance
test a survey meter before first using it on a given day and should
test it as often as necessary thereafter to be assured that the meter
is functioning satisfactorily.
4. When a meter is performance tested, the meter reading must fall
within ±10% of the check source reading indicated on the label
affixed to the meter. Any meter whose response does not fall within
this range is considered nonfunctional and should be taken out of service.
When a survey meter is not functioning properly or needs to be repaired
for any reason, the Office of Environmental Health and Safety should
be notified since the Office of Environmental Health and Safety maintains
repair and calibration records for each survey instrument and can offer
limited diagnostic and repair services.
5. All portable radiation survey instruments must be periodically calibrated
using the calibration service provided by the Office of Environmental
Health and Safety and must be calibrated following servicing or repair.
Routine calibrations are scheduled by the Office of Environmental Health
and Safety; the "Authorized User" is notified concerning the
calibration details. When a meter has been sent out for repair and has
been returned, the "Authorized User" must notify the Office
of Environmental Health and Safety to arrange for the meter's calibration.
Operational Work Area Surveys (top)
Survey Requirements
In addition to the routine surveys made by the Health Physics staff,
laboratory personnel manipulating open sources of radioactive materials
shall conduct operational work area surveys. These surveys shall be
performed using portable survey meters and/or wipe testing, as appropriate.
Surveys must be performed:
- At the end of an experimental procedure and at the end of each day
for multi-day procedures;
- During the manipulation of millicurie quantities of open sources
(the frequency and exact timing of this type of survey is left to
the judgment of the individual performing the experiment);
- Following withdrawals from stock sources containing millicurie quantities.
Records of such surveys must be kept. The records should include the
name of the surveyor, the date, the survey results, whether positive
or negative, and follow-up actions taken if contamination is found.
Action Levels
Paragraph 10.D.3 provides limits for permissible levels of removable
contamination on surfaces in restricted areas. When the operational
work area survey indicates the presence of contamination on surfaces,
e.g., floors, walls, bench tops, etc., in excess of the limits specified
in Paragraph 10.D.3, prompt decontamination is required. However, prompt
decontamination is encouraged when contamination levels exceed 100 dpm/100
cm2 for all beta, gamma or X-ray emitters and at 10 dpm/100 cm2 for
alpha emitters.
In the event substantial contamination is found, e.g., in an amount
exceeding the quantity specified in Appendix
C or if contamination is
widespread, the "Health Physicist" must be notified immediately.
Removable Contamination Limits
The limits for removable contamination on surfaces, e.g., work surfaces,
floors, walls, etc., in restricted areas are:
| |
Alpha Emitters |
Beta, Gamma, or X-Ray Emitters |
Low Risk Beta, Gamma, or X-Ray Emitters* |
| Surfaces in the Restricted Area |
220 dpm per 100 cm2 |
2200 dpm per 100 cm2 |
22,000 dpm per 100 cm2 |
*Low risk beta, gamma, or X-ray emitters are those isotopes with beta
energies less than 0.2 MeV, and/or gamma or X-ray emissions less than
0.1 R/hr at 1 meter per curie and with permissible air concentrations
greater than 10-6 microcuries per milliliter.
Personal Surveys (top)
Survey Requirements
When manipulating open sources of radioactive material, thorough surveys
of one's person and clothing must be performed, using portable survey
meters and/or wipe testing, as appropriate. Surveys must be performed:
- At the end of an experiment and at the end of each day for multi-day
procedures
- During manipulation of millicurie quantities of open sources (the
frequency and exact timing of this type of survey is left to the
judgment
of the individual performing the experiment)
- During and following the opening of radioactive material packages
- Following withdrawals from stock sources containing millicurie quantities;
- Prior to exiting the restricted area.
Records of such surveys must be kept. The records should include the
name of the surveyor, the date, the survey results, whether positive
or negative, and the follow-up actions taken if contamination is found.
Action Levels
Paragraph 10.E.3 provides limits for permissible levels of contamination
on personal protective clothing and the skin. When a survey indicates
skin contamination in excess of these limits, immediate efforts to decontaminate
the skin are required. However, decontamination of the skin is encouraged
at any level of contamination. Cases involving contamination of the
skin, regardless of the quantity, must be reported to the "Health
Physicist."
Contamination on clothing in excess of the limits specified in paragraph
10.E.3 requires that the contaminated clothing be removed promptly.
Prompt decontamination of clothing is encouraged at 100 dpm/100 cm2
for all beta, gamma or X-ray emitters and at 10 dpm/100 cm2 for alpha
emitters.
Contamination Limits
The limits for contamination on personal protective clothing and the
skin are:
| |
Alpha Emitters |
Beta, Gamma, or X-Ray Emitters |
Low Risk Beta, Gamma, or X-Ray Emitters* |
| Personal Protective Clothing |
220 dpm per 100 cm2 |
2,200 dpm per 100 cm2 |
22,000 dpm per 100 cm2 |
| Skin |
220 dpm per 100 cm2 |
220 dpm per 100 cm2 |
2,200 dpm per 100 cm2 |
*Low risk beta, gamma, or X-ray emitters are those isotopes with beta
energies less than 0.2 MeV, and/or X-ray emissions less than 0.1 R/hr
at 1 meter per curie and with permissible air concentrations greater
than 10-6 micro-curies per milliliter.
Smoking and Eating Restrictions (top)
- Eating, drinking, and smoking is prohibited in laboratories where
open sources of radioactive materials are used. Food for human consumption
shall not be placed or stored in any equipment such as refrigerators,
freezers or ovens in which radioisotopes are stored or used.
- For state-licensed radioactive materials (naturally-occurring or
accelerator produced radioactive materials which may include such
isotopes as H-3, Be-7, Na-22, Cr-51, Mn-54, Fe-55, Co-57, Zn-65, Cd-109,
In-111, Bi-210, Ra-226 and its progeny, and natural uranium and thorium),
additional restrictions apply. Eating, drinking, smoking and the application
of cosmetics is prohibited in any laboratory in which state-licensed
radioisotopes in sealed or open form are stored or used.
Protective Clothing (top)
Appropriate protective clothing, including gloves, a full-length laboratory
coat, shoes and socks, should be worn at all times for work with any
open radioactive source. Gloves, a full-length laboratory coat, shoes,
and socks are required to be worn by any person working with an open
radioactive source in an amount equal to or exceeding 0.01 times the
quantity given in Appendix C for any radioisotope, if such work creates
a reasonable potential for contamination. For the most commonly used
isotopes, these quantities are 1 mCi for C-14, 10 mCi for H-3, 0.01
mCi for I-125, 0.1 mCi for P-32, and 1 mCi for S-35.
Wearing sandals or open-toed shoes, when handling the quantities specified
above, is prohibited.
In-house Movement of Radioisotopes (top)
Radioisotopes moved within a building should be moved in such a way
that no radioactive material can be readily released from its container
under normal conditions and with sufficient forethought to minimize
the spillage of radioactive material. The inner container must be marked
"RADIOACTIVE" during transport and shielding must be provided
as needed. Radioactive material may not be left unattended during transit.
These precautions become especially important when radioactive material
is moved through unrestricted areas.
NOTE: Section 14 describes requirements for the intra-campus and off
campus transportation and shipment of radioactive materials.
Fume Hoods and Glove Boxes (top)
Experiments involving the use of open radioactive sources which could
result in airborne radioactivity should be carried out in fume hoods
or glove boxes. Because even ordinary laboratory manipulations can result
in the release of airborne radioactivity, all "Users" are
strongly urged to use a chemical fume hood for any physical or chemical
manipulation of radioisotopes. The "Health Physicist," during
review of an application for authorization, will determine whether use
of a fume hood or glove box is required and, if so, will make it a condition
of approval for the application.
Any use of a biological safety cabinet for radioactive materials should
be discussed beforehand with the "Health
Physicist." Under certain circumstances, biological safety
cabinets are not suitable, for instance, for volatile substances such
as radioiodine, since in many cases some air from the cabinet is exhausted
to the room.
Except as noted below, hoods for radioisotope work must have an average
face velocity of at least 50 linear feet per minute. Experiments involving
alpha-emitting radioisotopes and radioiodines must be performed in hoods
with an average face velocity of at least 95 linear feet per minute.
Hood and glove box surfaces should be protected to prevent contamination
of fixed surfaces that may be difficult to decontaminate.
In consideration of University maintenance personnel who may be called
to repair possibly contaminated hoods, all hoods which have been used
for radioisotope work are labeled by the Office of Environmental Health
and Safety, "This Hood used for Radioactive Material." Any
"User" who wishes to use an unlabelled hood for radioisotope
work should obtain the proper label from the Office of Environmental
Health and Safety.
Airborne Radioactivity (top)
For experiments that may result in the release of airborne radioactive
material, a routine air sampling and bioassay program may be required.
No operation may be planned and performed that will knowingly result
in the release of airborne radioactivity in excess of regulatory limits.
The "Health Physicist," during review of an application for
authorization, will evaluate the proposed procedures for any potential
for airborne releases. If the "Health
Physicist" determines that significant airborne radioactivity
is likely to be generated, air sampling will be made a condition of
approval of the application.
Caution: It should be remembered that the use of volatile or powdered
radioisotopes may result in significant airborne concentrations of radioactive
material.
Pipetting (top)
Mouth pipetting of radioactive material is prohibited.
Trial Runs (top)
Work which requires extensive physical and/or chemical manipulation
of radioisotopes should not be performed using radioactive material
until the techniques, procedures, and equipment have been tested in
a trial run. Under certain circumstances, e.g., when an unusually large
quantity of radioactive material, a particularly hazardous form of radioactive
material, or a new and untested procedure is proposed to be used, the
"Health Physicist" may determine that a trial run must be
performed before the procedure is carried out using radioactive materials,
or, if the use of radioactive materials in the trial run is unavoidable,
may determine that a trial run using smaller amounts of radioactive
material must be performed. When appropriate, such a requirement will
be made a condition of approval for authorization.
Working Surfaces (top)
All work involving physical or chemical manipulation of open radioactive
sources shall be performed directly on work surfaces suitable for containment
of contamination and easy decontamination. The lining of work surfaces
with plastic backed absorbent paper has been found to reduce the spread
of contamination.
Labeling (top)
Although labeling of equipment and containers is required only under
certain conditions (see Section 9), it is
good practice to label all contaminated objects and work surfaces to
indicate the presence of radioactive material. Such labeling reduces
confusion and prevents others from unsuspectingly using contaminated
equipment.
Opening of Shipments (top)
The opening of shipments of radioisotopes must be done in a properly
equipped laboratory and only by the "Authorized
User" or by an adequately trained individual designated by
the "Authorized User." Additional details are found in Section
8.
Security (top)
Visitors to laboratories using "Sources
of Radiation" should be supervised by a member of the laboratory
staff who is familiar with the activities of the laboratory. All radioactive
stock materials and sealed sources must be stored in a secured container
or secured storage area when not in use. Any room in which an unattended
sealed source is being used must be secured. Exceptions must be approved
in writing by the Office of Environmental Health and Safety (EHS). A
stock material is defined to be radioactive material as provided by
the vendor and does not include material withdrawn from the original
stock by a researcher for experimental use. This policy applies to materials
for which EHS approval and authorization is required and does not apply
to generally-licensed devices, such as smoke detectors, static eliminators,
electron capture detectors, exit signs, etc.
Special Equipment and Requirements (top)
In cases where the use of radioactive material presents unique or unusual
hazards, special radiation safety equipment, precautions, and procedures
may be required as determined in consultation with the "Health
Physicist." These might include specialized shielding and equipment,
clothing, monitoring equipment, etc. When appropriate, such requirements
will be made conditions of approval for authorization.
Animal Use and Care (top)
The use and care of animals used for in vivo experiments with radioisotopes
must be done in compliance with the provisions of the Animal Welfare
Act of 1970 and amendments thereto, as determined by the Animal
Care Subcommittee of the University Research Board. In addition
to those requirements, consideration must be given to the special problems
of animal waste collection, the disposal of carcasses, airborne radioactivity
resulting from exhaled radioactive materials, and the cleaning and decontamination
of cages. Required precautions, as determined by the "Health Physicist,"
will be made conditions of approval for authorization.
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