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HOT STUFF! Emergency Procedures in Rad Labs: Radioactive Material Spills

Posted on February 5, 2018

HOT STUFF! Emergency Procedures in Rad Labs: Radioactive Material Spills

 

We hope it won’t happen, we never look forward to it, but sooner or later we are all faced with radioactive material spills. Preparedness can make the difference between a controlled situation and a disaster. Knowing what to do in an emergency and having the proper materials on hand are essential for safe, efficient handling of spilled radioactive materials in the laboratory. The Nuclear Regulatory Commission (NRC) provides model spill procedures in Regulatory Guide 10.8, Revision 2, Appendix J. Or the licensee may develop his or her own procedures, In which case he/she Is encouraged to consider for inclusion all the items listed in the model procedure. The following procedures incorporate Appendix J (Model Spill Procedures) of Regulatory Guide 10.8, Revision 2.

NOTIFY OTHERS OF THE SPILL

Adjust your response to the seriousness of the spill. Instruct personnel present in the room at the time of the spill to evacuate the immediate area of the spill. but remain within the restricted area to prevent spreading the contamination. “Evacuated” personnel should not eat, drink, or smoke until they are monitored (hands, clothing, and shoes) and found to be free from contamination. Report all spills to supervisors and to the Radiation Safety Office. For a major spill, the area should be cleared of all persons not involved In the spill and the RSO should be notified immediately.

CONTAIN THE SPILL

Give attention first to personnel health and safety. If the spill is serious (see Table 1), put on the proper clothing and equipment for clean-up. In serious

Table 1.

accidents, close off and vacate the premises, and contact the Radiation Safety Office (post the numbers near the telephone). For minor spills, proceed with clean-up operations. If the material is a liquid, place an absorbent material such as paper towels, tissues, both or similar materials over the spill to prevent its spread. If the material Is a powdered solid, attempt to complain its spread by covering the area with a protective barrier such as a drip tray, empty beaker, or section of kraft paper. Remember that any materials used to soak up or pick up radioisotopes are contaminated and must be handled accordingly, with clean-up materials disposed of in radioactive waste containers. If appropriate, close doors and windows and turn off the room ventilation fans. If the spill is major, contain it but do not attempt to clean it up. Limit the movement of all personnel who may be contaminated. For an exposed source, shield it if possible, but only if this can be done without further contamination or a significant increase in radiation exposure. Close and lock the room, or otherwise secure the area to prevent entry.

Table 1. Action level criteria for common radionuclides (major vs. minor spills)

DECONTAMINATE THE AREA

Radiation Alert Ranger

Plan ahead by assembling a spill kit containing several pairs of disposable gloves, blotting material. ziplock plastic bags (for the radioactive waste), disposable shoe covers (if you have them), radiation caution tape, a couple of markers, and the Radiation Safety Office telephone number. These items can be kept in II half-gallon or gallon size ziplock bag. (Table 2 is a more comprehensive list of recommended items for a spill kit from Regulatory Guide 10.8.) When disposing of the contaminated cleaning materials remember to fold the absorbent paper with the clean side out and place it, along with contaminated gloves and other contaminated disposable material, in a plastic bag for transfer to a radioactive waste container. Consider what would constitute adequate protection and supplies for personnel involved in the dean-up if a spill occurred in your laboratory. Check your facility’s radiation safety guide for specific decontamination procedures. Once you have read this article (or at your next laboratory meeting) discuss with your co-workers what type of spill could occur in your laboratory, what the appropriate actions are, and assemble the above-mentioned items.

Table 2_ NRC recommended supplies for a spill kit

 

MONITOR THE AREA

Using appropriate survey techniques. monitor the area of the spill for contamination. starting well away from the spill to determine where the contamination actually starts. Also survey the surrounding areas to determine if the contamination has spread elsewhere. Monitor all personnel (hands, clothing, and shoe tops and sales) and materials, and decontaminate if necessary, before releasing them to clean areas. An easy general guide is to consider anything over twice background as being contaminated. (Table 3 gives the NRC recommended action levels for removable surface contamination.)

Using appropriate survey techniques. monitor the area of the spill for contamination. starting well away from the spill to determine where the contamination actually starts. Also survey the surrounding areas to determine if the contamination has spread elsewhere. Monitor all personnel (hands, clothing, and shoe tops and sales) and materials, and decontaminate if necessary, before releasing them to clean areas. An easy general guide is to consider anything over twice background as being contaminated. (Table 3 gives the NRC recommended action levels for removable surface contamination.)

Notify the radiation safety officer. The RSO will follow-up on the clean-up, document the incident, and, if necessary, contact the NRC. The NRC Radioactive Spill Report (see Figure 1) and Radioactive Spill Contamination Survey Form (see Figure 2) or the licensee’s own forms may be used to report spills to the NRC.

In short, NOTIFY, CONTAIN, DECONTAMINATE and MONITOR. Note that this sequence of steps is appropriate for many emergency situations, even if they do not involve radioactive materials. If you are unsure whether you should call your Radiation Safety Office. call. ‘TIS BETTER TO BE SAFE THAN SORRY.

Table 3 . Recommended action levels {or removable surface contamination(a)

(a) Adapted from US NRC Regulatory Guide 8.23. Rev. 1, “Radiation Safety Surveys at Medical Institutions, n January. 1981

(b) Low-risk nuclides include C14, H3, S35, Tc99m, and others whose beta energies are less than 0.2 MeV maximum, whose gamma- or x-ray emission is less than 0.1 R h-1 at 1 meter per curie, and whose permissible concentration in air is greater than 10-6 microCi ml-1
Figure 2. Radioactive Spill Contamination Survey. (Exhibit 11, Regulatory Guide 10.8)

Reference
I. U.S. Nuclear Regulatory Commission, “Guide for the Preparation of Applications for Medical Use Programs,” Regulatory Guide 10.8. Revision 2, USNRC, Washington, DC 20555, August 1987.

Figure 1. Radioactive Spill/ Report (Exhibit 10, Regulatory Guide 10.8)

The Author
Ron Fritz has been a health physicist with Michigan State University (Office of Radiation, Chemical, and Biological Safety) since 1991. He is involved with radiation protection, NRC broad license compliance issues, x-ray quality assurance measurements, analytical x-ray safety, microwave and electromagnetics safety, and laser eye safety. His previous experience includes seven years in microwave engineering. six years as an engineer in anti-submarine warfare, and five years teaching community college and high school physics. He is co-holder of a patent for a method of microwave materials processing.

Ron Fritz
Health Physicist
Office of Radiation. Chemical and Biological Safety
Michigan State University
C-124 Research Complex-Engineering
East Lansing. MI 48824

 

Article Reprinted from RSO Magazine – July/August 1997

 

 

 

 

 


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