Answer to Question #3753 Submitted to "Ask the Experts"

What is the proper cleanup when a tritium-powered exit sign has been broken? What precautions should be observed while handling the broken sign? How should one dispose of the broken sign?

We note that your email address domain is that of a manufacturer/distributor of such signs. You should determine if the Nuclear Regulatory Commission or state license that authorizes the distribution of these signs contains requirements for content of the guidance you requested and, if so, you should follow them. If such guidance has not been incorporated into the license, it would be prudent to ask the licensing agency if it wishes to review it.

Absent such requirements, the following guidance is suggested for use by a member of the public involved in breakage of a tritium sign. It is not intended to cover breakage of such devices within a licensed facility where the use and possession of the sign is covered by a specific license.

It reflects good health physics practice to take into account the potential radiation hazard from the tritium and the manner in which it is incorporated into the sign based on a guide prepared by the New Jersey Department of Environmental Protection for dealing with broken exit signs containing tritium. When a tritium exit sign is broken, precautions should be taken to reduce the possible radiation dose to an individual residing in the area where the incident occurred as well as individuals assigned for cleanup.

When an Exit Sign Containing Tritium (³H) Is Damaged (broken with the release of ³H):

1. Evacuate the area immediately.
2. Ventilate the area to the outside.
3. Isolate the area; do not allow entry.
4. Identify all individuals possibly exposed to the H-3.
5. Individuals possibly exposed should immediately:
   
   • Shower with soap and water (or at least wash face and hands).
   • Change clothing (retain in plastic bag).
   • Drink plenty of fluids.
   • Collect a urine sample immediately and then 24-hour cumulative samples and follow Nuclear Regulatory Commission (NRC), state, or health physics consultant advice on where to send them for analysis.
6. Call the NRC Regional Office.
7. Call the State Radiation Protection Program.
8. Call manufacturer of signs for technical information.
9. Be prepared to hire a health physics consultant to deal with initial monitoring, decontamination, and disposal of the exit sign and contaminated materials.

The protective clothing required for cleanup usually consists of gloves and booties. The broken sign should be placed in an air-tight container by a health physics consultant. If silica gel is available it should be placed in the container with the broken sign. The silica gel will collect tritiated water. At a minimum, the broken sign and any miscellaneous pieces should be double bagged and sealed in plastic. Disposal of the broken sign should be arranged through the manufacturer or a health physics consultant. A list of manufacturers who may be contacted for disposal of a tritium sign (or any other tritium-containing device) is on the New Jersey Radiation Control Program Web site.

Additional references:

1. Pacific Northwest Laboratories, PNL-10620, Tritium Radioluminescent Devices Health and Safety Manual; June 1995.
    
2. US Department of Energy, DOE/EH-0201T, Recommended Tritium Surface Contamination Release Guides; March 1992.

Jill Lipoti
New Jersey Department of Environmental Protection