ML20059D414

Safety Evaluation Which Supports Granting of Exemption, Per 10CFR20.501

ML20059D414
Person / Time
Site:	South Texas
Issue date:	12/30/1993
From:	Office of Nuclear Reactor Regulation
To:
Shared Package
ML20059D405	List: ML20059D402 ML20059D414
References
NUDOCS 9401070255
Download: ML20059D414 (4)

Text

0 gTTEGuq 371 UNITED STATES i

E-NUCLEAR REGULATORY COMMISSION E

WASHINGTON, D.C. 20556-0001 49.....,o P

SAFETY EVALUATION BY THE OFFICE OF NUCLEAR REACTOR REGULATION RELATED TO THE USE OF SORBENT CANISTERS FOR PROTECTION AGAINST RADI0 IODINE HOUSTON-LIGHTING & POWER COMPANY CITY PUBLIC SERVICE BOARD OF SAN ANTONIO CENTRAL POWER AND LIGHT COMPANY CITY OF AUSTIN. TEXAS SOUTH TEXAS pRDdECT. UNITS 1 AND 2 D90KET N05. 50-498 AND 50-499

1.0 INTRODUCTION

Houston Lighting & Power Company (HL&P, the licensee) in its letter dated December 19, 1991, as supplemented by letters dated July 1,1993, and November 3,1993, requested approval by the NRC of its use of iodine sorbent respirator canisters. The proposed maximum time of use for any individual canister is 8 hours9.259259e-5 days <br />0.00222 hours <br />1.322751e-5 weeks <br />3.044e-6 months <br />. The use of such respiratory protection equipment is not authorized by the Commission's regulations, and footnote d-2(c) to Appendix A to.10 CFR Part 20, explicitly prohibits allowance for the use of sorbents against radioactive gases or vapors. However, Section 20.501 of 10 CFR Part 20 provides for the Commission's granting of exemptions from its regulations, and Section 20.103(e) specifies the necessary basis for approval.

Test data and canister qualification information have been provided by the i

licensee to support an exemption to allow the use of a radioiodine protection factor of 50 for Mine Safety Appliance (MSA) GMR-1. canisters at the South Texas Project, Units 1 and 2.

2.0 EyALUATION i

A National Institute for Occupational Safety and Health /Mine Safety and Health Administration (NIOSH/MSHA) testing and certification schedule for sorbents to -

4 be used for protection against radioiodine gases and vapors has not been implemented. Therefore, in accordance with paragraph 20.103(e) of 10 CFR Part 20, the staff has evaluated the licensee's request and verified that the licensee has demonstrated through reliable test data and adequate quality j

assurance measures that the material and performance characteristics of the

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MSA GMR-I canister are capable of providing the proposed degree of protection l

l 9401070255 931230 PDR ADOCK 05000498 P

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. '(i.e., a protection factor of 50) under the anticipated conditions of use for 8 hours9.259259e-5 days <br />0.00222 hours <br />1.322751e-5 weeks <br />3.044e-6 months <br />. Canister efficieno and service life, and the effects of temperature, poisons, relatt.e humidity, challenge concentration and breathing rates on canister efficiency and service life were considered. The evaluation of the licensee's program for the use of the canisters included quality control / quality assurance, and radiation protection /as-low-as-reasonably-achievable (ALARA) considerations, including task preparation and planning, on-the-job and post-task evaluations,.the use of engineering controls, radiological surveillance, and radiological safety training.

The licensee has provided reliable test information verifying that the MSA GMR-I canister is capable of providing a protection factor of 50 over a period of 8 hours9.259259e-5 days <br />0.00222 hours <br />1.322751e-5 weeks <br />3.044e-6 months <br /> of continuous use, provided that the total challenge of radioactive and non-radioactive iodine and other halogenated compounds does not exceed 1 ppm, and temperature does not exceed 110*F provided the. dewpoint does not exceed 107*F. The data showed the breakthrough point to be well beyond 8 hours9.259259e-5 days <br />0.00222 hours <br />1.322751e-5 weeks <br />3.044e-6 months <br />.

Testing has been conducted under acceptable conditions of cyclic flow, and under worst case conditions for those environmental factors affecting service life (i.e., temperature, relative humidity, and challenge concentration of CH 1 (methyliodide/ methyl radio Mdide), the most penetrating of the challenge 3

forms). The data showed that th MSA GMR-I canisters performed adequately under acceptable test conditions These conditions, including criteria and test methods are consistent with Cnse derived by the NRC staff from NUREG/CR-3403 for the canisters and are acceptable.

The licensee, through acceptance of MSA QA controls, has provided commitments that the MSA GMR-I canisters will meet standards for quality assurance and quality control that are recognized by NIOSH, are compatible with NRC staff positions, and are, therefore, acceptable.

This includes a commitment to establish a 1 percent. AQL (acceptable quality limit) in a 5 to 10 ppm challenge concentration of CH 1, 90 percent relative humidity,110*F, 64 3

liters per minute cyclic flow, for a service life of 8 hours9.259259e-5 days <br />0.00222 hours <br />1.322751e-5 weeks <br />3.044e-6 months <br /> or more at a penetration equal to 1 percent of the challenge concentration. Test data referenced by the licensee demonstrate that performance (i.e., service life) of canisters at 100 percent relative humidity is acceptable.

The licensee's proposed protection factor of 50 over an 8-hour time period is acceptable for the canisters when coupled with a full face facepiece respirator with the capability of providing a fit factor equal to or greater--

than 500 by quantitative fit test. As indicated above, test results show that.

canister efficiency will be retained for the radioiodine-gas or vapors of interest (CH 1,1, HOI) for this time period. To help prevent canister 3

2 deterioration from aging, canister service life will be limited to 8 hours9.259259e-5 days <br />0.00222 hours <br />1.322751e-5 weeks <br />3.044e-6 months <br /> from the time of canister unsealing. Canisters will be stored in sealed humidity-barrier packaging in a relatively cool, dry environment, and discarded after the 8 hour9.259259e-5 days <br />0.00222 hours <br />1.322751e-5 weeks <br />3.044e-6 months <br /> service period to prevent reuse. Through usage restrictions, based, in part, on air sampling, the licensee will preclude canister exposures to organic vapors and chemicals (such as decontamination compounds, lubricants, volatized paint solvent, alcohols, and freon) and temperatures in excess of 110*F, which could accelerate aging or poisoning of the sorbent, or desorption of the absorbed radiciodines.

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9 9 - 3.0 LIMITATIONS. PRECAUTIONS AND RESTRICTIONS Certain limitations and precautions based on NUREG/CR-3403, " Criteria and Test Methods for Certifying Air-Purifying Respirator Cartridges and Canisters Against Radiciodine," guidance are necessary for utilization of the sorbent canisters. The staff agrees with the following limitations and usage rwtrictions as proposed by the licensee:

1.

The protection factor shall not exceed 50.

2.

The maximum permissible continuous "use" time is 8 hours9.259259e-5 days <br />0.00222 hours <br />1.322751e-5 weeks <br />3.044e-6 months <br /> after which the canister shall be discarded.

"Use" time includes all elapsed time following unsealing of a canister.. In other words, a canister shall be discarded 8 hours9.259259e-5 days <br />0.00222 hours <br />1.322751e-5 weeks <br />3.044e-6 months <br /> after l't is first unsealed.

3.

Canisters shall not be used in the presence of organic solvent vapors.

4.

Canisters shall be stored in air-conditioned areas with temperatures-averaging less than 90*F, and protected from the external environment, physical damage, and airborne contaminants.

5.

Canisters shall be used with a full face facepiece respirator capable of providing a fit factor greater than 500 as established by a quantitative fit test.

6.

Canisters shall not be used in total challenge concentrations of organic iodines and other halogenated compounds greater than 1 ppm, including nonradioactive compounds.

7.

Canisters shall not be used in environments where temperatures are greater than 110*F.

In addition to the limitations and usage restrictions noted above, the following additional controls shall be utilized by the licensee:

1.

Canister site-of-use temperatures-shall be measured prior. to and/or during the use of GMR-I canisters to assure that temperatures do not exceed 110*F.

2.

Air samples shall be taken and analyzed prior to and during any activities that involve the use of the GMR-I canister for protection against radioactive iodine.

3.

Weekly whole body counts shall be performed on each individual using GMR-I canisters for radiciodine protection.

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,.. 4.

A whole body count shall be performed on each individual shown to have exceeded 10 maximum permissible concentration-hours in a week and who used the GMR-I canister for respiratory' protection in that period prior to that individual's next entry into a radiciodine atmosphere.

5.

Anyone that measures 70 nCi or greater iodine uptake to the thyroid during a whole body count shall not enter a r&dioiodine atmosphere pending health physics evaluation.

6.

Applicable radiological survey and whole body count information shall be compiled and used to evaluate the effectiveness of the.

licensee's use of the sorbent canisters.

7.

Specific plant procedures shall be revised to explicitly incorporate the limitations and controls stated above.

4.0 CONCLUSION

The staff concludes that the licensee's proposed use of radiciodine MSA GMR-1 canisters with certain usage restrictions and controls will provide effective protaction and is acceptable. The licensee has provided. usage restrictions and controls which can assure an effective radiolodine protection program.

The proposed criteria and test methods for verifying the effectiveness and quality of GMR-1 canisters are consistent with the staff's criteria. The proposed exemption, with the controls and limitations, meets the staff's positions in Regulatory Guida 8.8 "Information Relevant to Ensuring that' Occupational Radiation Exposures at Nuclear Power Stations Will Be As Low As Reasonably Achievable" and NUREG/CR-3403. The actions proposed by the licensee are. consistent with the requirements of 10-CFR 20.103(e)..The staff agrees that the licensee has provided an acceptable basis to authorize the use of equipment (MSA GMR-1 canisters) in accordance with-10 CFR 20.103(c), and that the granting of an exemption is in accordance with the provisions of 10-CFR 20.501, which is authorized by law and will not result in undue hazard to life or property.

Principal Contributor:

J. Bell, NRR L. Kokajko, NRR Date:

December 30. 1993 l

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