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RADIATION SAFETY MANUAL
Section 10 : Accident, Spill and Decontamination Procedure

INDEX
10.1 Legislative Requirements
10.2 Radiation Accident Procedure
10.3 Radiation Spills - Action to be Taken
10.4 Decontamination Procedures
10.5 Reporting to the Environment Protection Agency

10.1 LEGISLATIVE REQUIREMENTS
Within the meaning of the Radiation Control Act (1990) certain accidents are taken to be radiation accidents. These must be formally reported to the EPA.

10.1.1
For the purposes of this Regulation, a radiation accident is to be treated as having occurred if there is an occurrence that involves the unplanned and unexpected emission of radiation (such as spillage or leakage of a radioactive substance or damage to radiation apparatus) and that is of such a nature or extent that it is likely:
 
(a) that one or more persons have, or could have, received a dose of radiation equal to or in excess of:
 
(i) 5 millisieverts, in the case of an occupationally exposed person; or
(ii) 1 millisievert, in any other case; or
(b) that premises or the environment may have become contaminated within the meaning of section 21 of the Act.

10.1.2 General Working Rules for all X-ray Analysis Units
For the purposes of this Regulation, a radiation accident is to be treated as having occurred if there is an occurrence that involves the misuse of radiation apparatus.

(a) administration of a therapeutic dose of radiation from radiation apparatus or a sealed radioactive source which differs from the prescribed treatment dose by more than 10 per cent.;
(b)

the unintended administration of radiation as a result of a malfunction of radiation apparatus.

10.2 RADIATION ACCIDENT PROCEDURE
In the case of accidental irradiation or accidental contamination or ingestion or radioactive material by any member of staff, student or a visitor, the following procedure should be followed:

10.2.1 The person involved shall report the incident to their immediate supervisor, who shall report it immediately to the Departmental/building Radiation Safety Officer. If external contamination is involved, the contaminated person must be encouraged to remain, if practicable, in the immediate area to prevent spread of contamination.
10.2.2 The Departmental/Building Radiation Safety Officer shall make an initial assessment of the situation and, unless the incident is of a minor nature, and in case of any doubt, the University Radiation Safety Officer must be immediately notified. It is sometimes difficult to reconstruct an accident. It is therefore recommended that all persons involved write a brief (1 paragraph) report of the accident situation as soon as feasible after the incident. It should be encouraged that these reports are written independently and without discussion of the persons involved.
10.2.3 The Departmental/Building Radiation Safety Officer investigates the situation, recommending any immediate action that may be taken, such as decontamination.
10.2.4 Each situation shall be considered separately, but in every case an estimate shall be made as soon as possible of any personal radiation dose as a result of the incident. If this dose exceeds 0.5 Gy, then the person is required to be admitted to hospital and placed in isolation. This would be an extreme situation and unlikely to occur at the University of Newcastle with the levels of isotopes currently used. A Radiation Oncologist and Haematologist should be consulted in such cases.
10.2.5 In appropriate cases the Radiation Safety Officer shall carry out an investigation and produce a report to the University Radiation Safety Officer. Incidents involving radiation are subsequently presented to the Radiation Safety Committee for consideration. Guidelines on reporting of radiation incidents are to be found in Section 10.
10.2.6 Any recommendations made as a result of the incident and approved by the Radiation Safety Committee and Occupational Health and Safety Committee and forwarded to the section concerned as soon as possible and the University Radiation Safety Officer may, at some later date, make a follow up investigation to discuss implementation of any recommendations.

10.3 RADIATION SPILLS - ACTION TO BE TAKEN

10.3.1

Action Flow Chart - Remember to report the spill to the supervisor or section/laboratory manager or Building RSO

“Hot” is defined as significantly above background given knowledge of the isotope, specific activity and characteristics of the measuring instrumentation. And type and energy of the radiation being measured. “Disposal of Waste” refers to storage in the appropriate “Bunker” to allow decay.
10.3.2 Post Mortem
 

Please examine your procedure - was the spill avoidable? Unless the spill is very minor, the School/Building Radiation Safety Officer must be notified and a Accident Form completed.

10.4 DECONTAMINATION PROCEDURES
Decontamination is the removal of radioactive contamination from animate and inanimate surfaces. If contamination is found it must be removed at once. High specific activity isotopes can be held on a surface by ionic attachment, or by physical absorption or diffusion into cracks. Often a fresh spill on a clean and polished surface can be washed off without detectable residual contamination, where if it were allowed to react with the surface it might need drastic action to remove it. This is a very good reason for monitoring a working space immediately after using radioactive material, and for removing contamination associated with spills as quickly as possible.

10.4.1 Environment
Although special decontaminations involving the use of acids, alkalis, complexing agents and ion exchange materials are available, it is best to first try simple methods such as soap and water (preferably distilled) or detergent unless a special decontaminant is specifically indicated.

In the event of a minor spill involving no radiation hazard to personnel, the operator (wearing rubber gloves) should proceed as follows:

Mark out the area with radiation marking tape and then for:

Wet spill: the liquid should be carefully wiped up with blotting paper or similar material.

Dry spill: the material should be carefully wiped up with absorbent tissue moistened with a 5% solution of glycerine in water. In the case of very active and toxic materials, which also present an ingestion hazard, a suitable face respirator should be worn.

All papers used in cleaning should be placed in a radiation waste receptacle and the affected areas monitored. Decontamination should be carried out until no further reduction in radiation levels, as checked by the Radiation Officer, is being achieved, provided that the contamination level is then below the maximum permissible.

After completion of all operations, the area must be checked with radiation monitoring equipment or, in the case of 14C and 3H, with a swab which can then be counted in the Scintillation counter.

IF THERE IS ANY DOUBT CONCERNING THE ABOVE PROCEDURES, ADVICE AND RULINGS SHOULD BE SOUGHT FROM THE SCHOOL/BUILDING RADIATION OFFICER.

10.4.2 Personnel

(i) Before using more vigorous techniques that risk breaking the skin and allowing radioactive material to enter the body, covering the contaminated area with plastic wrap( or plastic gloves if on the hand) for a period of time may allow sweating to loosen the contamination which can then be removed by gentle washing. This period can be up to 24 hours. The skin dose during that period is likely to be small and the risk of breaking the skin is avoided.
(ii) Wash gently with soap and water, avoiding contamination of the eyes and mouth. Do not scrub to avoid irritating the skin and "rubbing in" the activity. Monitor with a portable survey meter until the count rate is less than 1000 cps (or the exposure is less than 10 microgray/hr with the detector at a point close to the contaminated region of skin. These levels must be interpreted along with knowledge of the isotope concerned, its biological implications, its specific activity and type of energy , and the characteristics of the measuring instrumentation. If in doubt the Building RSO or University RSO should be contacted for advice.
(iii) If this fails, a paste of fuller's earth or Kaolin may be applied and subsequently washed off the soap and water.
(iv) If this fails, try E.D.T.A. solution (a chelating agent) followed by a nail brush, soap and water.
(v) As a last resort, immerse the hands or swab affected skin in saturated potassium permanganate solution, rinse in water and remove stain with 5 per cent solution of sodium bisulphite.

Mouth - wash out with hydrogen peroxide solution (1 tablespoonful of 10 volume hydrogen peroxide to a tumbler of water) several times.

Radioactive material in the eyes or nose - solid or liquid. Irrigate with saline (0.9 per cent common salt solution). If this solution is not available, use tap water. Care must be taken to avoid swallowing contaminated material.

Contamination of a Wound - wash under a tap with copious quantities of water and encourage bleeding. If the wound is on the face take care not to contaminate the eyes, mouth, or nostrils. Next, wash the wound with soap and water and apply disinfectant and first aid dressing.

All accidents involving significant contamination of personnel must be reported immediately to the University Radiation Safety Officer through the School/Building Radiation Officer.

All material used in decontamination or treatment of an injury must be collected and bagged and labelled for disposal once treatment has been completed.

Note: All materials listed above should be stored in easy access in the Radiation Rooms (Medium Level Laboratories).

10.5 REPORTING TO THE ENVIRONMENT PROTECTION AUTHORITY
Incidents which require notification to the EPA Radiation Control should be determined under the guidelines drawn up by the EPA. In the meantime, any incident where any of the following limits are exceeded should be reported to the Radiation Control Section of the EPA by the Radiation Safety Officer as soon as possible, but in any case, less than thirty days following the incident.

10.5.1 Exposure of an individual to radiation in excess of the maximum permissible annual dose for the relevant category of staff.
10.5.2 Concentrations of radioactive material in an unrestricted area in excess of 10 times the limit prescribed in the Radiation Control Act 1990 for the particular radionuclide.
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