United States Nuclear Regulatory Commission - Protecting People and the Environment

Farley 1 & 2 - 10 CFR Part 20 Exemption Request, MSA GMR-I Canister (Part No. 466220) Radioiodine Protection Factor

HPPOS-037 PDR-9111210173

See the memorandum from D. R. Muller to G. C. Lainas dated June 28, 1984. It recommended an exemption to allow licensees to use MSA GMR-I canisters for protection against iodine gases and vapors with certain restrictions. This action set a precedent. The health physics position was written in the context of 10 CFR 20.103, but it also applies to "new" 10 CFR 20.1703.

The Radiological Assessment Branch (RAB) reviewed a licensee's application for an exemption to 10 CFR Part 20, Appendix A, Footnote d.2 (c) to allow the use of MSA GMR-I Canisters. Although the action established a precedent, the RAB recommended, in accordance with the provisions of 10 CFR 20.103 (e) [or 10 CFR 20.1703 (a) (2)], that the exemption be approved with restrictions.

The restrictions were enumerated by the NRC staff in their Safety Evaluation Report and are summarized as follows:

  1. A protection factor of 50 for radioiodine gases and vapors was to be used.

  2. The MSA GMR-I Canisters were to be discarded after a maximum of 8 hours continuous use time.

  3. The MSA GMR-I Canisters were not to be used in the presence of organic solvent vapors.

  4. The MSA GMR-I Canisters were to be stored in sealed, humidity barrier packaging in cool, dry environments.

  5. The service life of the MSA GMR-I Canisters were to be calculated from the time of unsealing, including periods of non-exposure.

  6. The MSA GMR-I Canisters were to be used with a full facepiece capable of providing protection factors greater than 100.

  7. The MSA GMR-I Canisters were not to be used in total challenge concentrations of organic iodines and other halogenated compounds greater than 1 ppm, including nonradioactive compounds.

  8. The MSA GMR-I Canisters were not to be used in environments with temperatures greater than 110F. The above exemptions are subject to amendment by the NRC staff and will remain in effect until rescinded by NRC staff or superseded by regulation.

Regulatory references: 10 CFR 20.103, 10 CFR 20.1703, NUREG / CR-3403

Subject Code: 8.4, 8.10

Applicability: Reactors

Page Last Reviewed/Updated Thursday, June 04, 2015