ML18153A428

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Forwards Info Requested by NRC to Support Review of Equipment Authorization to Use Respiratory Protection Equipment for Equipment Which Has Not Been Tested & Certified by Niosh/Msha for Specific Application at Plants
ML18153A428
Person / Time
Site: Surry, North Anna  Dominion icon.png
Issue date: 07/28/1997
From: Ohanlon J
VIRGINIA POWER (VIRGINIA ELECTRIC & POWER CO.)
To:
NRC OFFICE OF INFORMATION RESOURCES MANAGEMENT (IRM)
References
97-092A, 97-92A, NUDOCS 9708010258
Download: ML18153A428 (7)


Text

VIRGINIA ELECTRIC AND PowER CoMPANY RICHMOND, VIRGINIA 23261 July 28, 1997 United States Nuclear Regulatory Commission Serial No. 97-092A Attention: Document Control Desk NL&OS/DAS RO Washington, D.C. -20555 Docket Nos. 50-280/281 50-338/339 License Nos. DPR-32/37 NPF-4/7

Dear Gentlemen:

VIRGINIA ELECTRIC AND POWER COMPANY SURRY POWER STATION UNITS 1 AND 2 NORTH ANNA POWER STATION UNITS 1 AND 2 REQUEST FOR ADDITIONAL INFORMATION 10 CFR 20.1703(a)(2) EQUIPMENT AUTHORIZATION In a March 27, 1997 letter (Serial No.97-092) Virginia Electric and Power Company requested specific authorization to use respiratory protection equipment for equipment which has not been tested and certified by NIOSH/MSHA for the specific application at both Surry and North Anna Power Stations. In a June 26, 1997 letter, the staff . i I

requested additional information. The attachment provides information requested by the Staff, to support the review of the equipment authorization.

Should you have any questions regarding the authorization request, please do not hesitate to contact us.

Very truly yours, James P. O'Hanlon Senior Vice President - Nuclear Attachment Commitments made by this letter:

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Region II Atlanta Federal Center 61 Forsyth St., SW, Suite 23T85 Atlanta, Georgia 30303 Mr. R. A. Musser NRC Senior Resident Inspector Surry Power Station Mr. M. J. Morgan NRC Senior Resident Inspector North Anna Power Station

Attachment 10 CFR 20.1703(a)(2) Authorization Request for Additional Information Virginia Electric and Power Company Surry and North Anna Power Stations

  • Virginia Electric and Power Company 10 CFR 20.1703(a)(2) Authorization Request for Additional Information
1. In the March 27-, 1997 request letter for the 10 CFR 20.1703(a)(2) authorization, Virginia Electric and Power Company requested to " .. make allowance for protection factors as specified for Pressure Demand Self-Contained Breathing Apparatus (SCBA) in 10 CFR 20, Appendix A (i.e., 10,000 or greater) during normal and emergency use." In reference to the numerical value of the SCBA protection factor (PF) 10,000 or greater, please confirm that you are requesting to use protection factors greater than 10,000. Since 10 CFR 20 Appendix A requires prior authorization to use PFs greater than 10,000, please provide additional test data for PFs greater than 10,000 tcrjustify use of such PFs. *

Response

Virginia Electric and Power Company (Virginia Power) does not -require the use of protection factors greater than 10,000 in conjunction with our containment use only (CUO) Pressure-Demand Self-Contained Breathing Apparatus (SCBA).

2. In Attachment 1 of the submittal, the SCBA maintenance program for the "containment-use only" (CUO) units is described mainly in general terms. The staff needs more details about CUO SCBA maintenance.
a. The site maintenance procedures and SCBA maintenance worker training program are "in accordance with MSA's [Mine Safety Appliances] training, and preventive maintenance and repair procedures." Please confirm if these vendor procedures are generic to open-circuit SCBAs, or are they specific for the CUO units. Also please describe aspects of the maintenance procedures and training programs which are specific to the CUO units and which differ from the generic MSA maintenance procedures and training program. This description should include different techniques (e.g., how to keep a hydrocarbon-free environment), routine inspection frequencies (e.g., 0-rings for regulator, steel cylinder hydrostatic tests}, or other routine maintenance activities.

Response

MSA and Virginia Power procedures require that all repairs to SCBA be made exclusively in accordance with "model specific" MSA guidance and by factory trained and authorized personnel. These procedures make it unacceptable for Virginia Power to maintain any SCBA equipment, including the containment-use only (CUO) units in question, in any manner other than as specified by MSA (e.g., all MSA SCBA are repaired in a hydrocarbon free environment). However, in the context of your question, MSA maintenance requirements are considered generic (applicable to all models) since specific maintenance procedures have not been developed for SCBA charged with 35% oxygen/65% nitrogen.

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As stated in our initial authorization request, Virginia Power procedures do contain some directions specific to CUO SCBA (e.g., charging cylinders with 35% oxygen/65% nitrogen), however, these differences are necessitated by operational requirements (i.e., use of a dedicated compressor or cascade system), not by manufacturer guidance.

b. Do the maintenance surveillance activities for SCBA units differ depending on whether brass or aluminum alloy components are used? If not, justify why not and provide a detailed maintenance/surveillance/inspection summary of any experience with CUO SCBAs (using enriched oxygen) with non-brass parts. The test data submitted in Attachments 2 and 3 of your March 27, 1997 request focused on *catastrophic SCBA failures, while this question is directed at a program for assessing chronic degradation (e.g., accelerated corrosion) of aluminum alloy parts and material used in an enriched oxygen environment.

Response

MSA does not direct that maintenance surveillance activities differ for SCBA units based upon whether brass or aluminum alloy components are used.

Virginia Power believes, and MSA agrees, that: 1.) the current inspection and maintenance frequencies specified are adequate to monitor SCBA material condition, and 2.) that the percentage increase of oxygen from 21 to 35 percent should not cause any significant increased rate of degradation in either brass, aluminum, or SCBA softgoods components.

Virginia Power currently does not allow the use of 35% oxygen/65% nitrogen charged SCBA which contain aluminum parts, therefore no experience history can be provided for aluminum components. Chronic degradation (e.g.,

accelerated corrosion) due to substitution of aluminum parts for brass, as stated above, is not anticipated. All degradation (chronic or abrupt) will continue to be monitored by the inspection, maintenance, and problem reporting programs mandated by Virginia Power procedures.

3. Relative to the requirements of 10 CFR 20.1703(a)(3)(v) (medical fitness evaluation), describe any special, additional information provided to the medical doctor for an evaluation of a worker who enters containment using an SCBA. If no special distinction is made among SCBA users, then justify why not, given the challenging containment environment. Have any site workers been approved for routine SCBA use, but not for in-containment use? If so, give the percentage of rejected versus approved workers.

Response

Virginia Power requires annual respiratory physicals be performed under the direct supervision of a licensed physician. The first step in this process is the completion of a detailed medical history form. The information on this form, in conjunction with follow-up questions and the actual physical examination, Page 2 of 4

supply the information necessary for the physician to make decisions concerning each employee's ability to enter containment. If temporary or permanent containment access restriction is indicated, then a Medical Testing Form is completed and forwarded to the employee in question and appropriate supervision.

Restriction from containment entry due to inability to wear SCBA for medical reasons is rare (i.e., < 1%). It is more common for employees to be excluded from entering containment due to overall health conditions that would be aggravated by the containment environment itself (i.e., high temperature, subatmospheric pressure, confined spaces). Examples of these restricting health conditions include inner ear problems, heart conditions, and muscular injuries.

Discussions with Company medical personnel indicate that there are currently

- -only two individuals at North Anna and Surry Power Stations who are approved to wear SCBA outside of containment (for emergency purposes), but are not allowed to make subatmospheric containment entries (wearing GUO SCBA).

One individual has insulin dependent diabetes, a condition that can result in the onset of insulin shock, especially under high stress conditions (e.g., containment heat and humidity). The other individual has advanced problems from sarcoidosis. Again, it is not the SCBA that is the limiting factor. Rather it is the concern that in the event of a medical emergency, help would be delayed due to restricted access I egress.

4. Relative to the user fit testing requirements, what pass-fail criteria is used to ascertain an acceptable fit? The NRC staff finds the guidance in 288.2-1992 acceptable -- for a positive-pressure, tight-fitting respirator, a fit factor of at least 100 should be obtained. What percentage of fit-testers for SCBA use have failed the existing site's fit testing criteria?

Response

Virginia Power fit testing procedures specify a minimum fit factor of 1000 (i.e., a safety factor of 20 applied to a full facepiece negative pressure respirator).

Additionally, Virginia Power does follow the guidance of ANSI 288.2-1992 in requiring fit tests for all tight-fitting respirators worn regardless of mode (e.g.,

individuals are required to obtain a satisfactory fit test even if the only tight-fitting respirator they may wear is a positive pressure device such as SCBA).

Virginia Power uses the MSA Ultravue facepiece available in both hycar rubber and silicone in small, medium, and large sizes. This combination has proven itself extremely successful in fitting a wide variety of potential employees (i.e.,

100%).

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5.

The CUO SCBAs are intended to be available for "emergency use." Does this include in-containment firefighting? If so, what prevents the temperature "limit" of 135 degrees Fahrenhl:lit (to prevent possible 0-ring failures during initial regulator startup) from being exceeded in containment?

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Response

Virginia Power intends, pending NRC approval, to allow the use of MSA Ultralite or Custom 4500 SCBA charged with 35% oxygen/65% nitrogen for containment firefighting. We intend to procedurally restrict Model 401 CUO SCBA to routine and emergency uses exclusive of fire fighting. The reason for this is NFPA 1981 (1992 Edition) which contains a performance *requirement in Appendix A (Heat and Flame Test). This stipulation increases the required regulator supplied flow rate from 40 Umin. to 100 Umin. The MSA Model 401 SCBA was designed before this requirement came into being. The MSA Ultralite and Custom 4500 do meet the-100 Umin. flow requirement.

Virginia Power believes the 135 degrees Fahrenheit "limit" (to prevent possible 0-ring failures during initial regulator startup) is not a problem for the following reasons:

  • CUO SCBA are staged outside of containment in a room temperature environment. In the event of a fire in containment under vacuum, CUO SCBA use would be initiated before ambient temperatures exceeded 135 degrees Fahrenheit.
  • 135 degrees Fahrenheit, as used by NASA in their Test Report, was not a failure temperature. It was the temperature that they did not test beyond, therefore conservatively limiting their approval to 135 degrees Fahrenheit.
  • NASA, during their Compressive Heating Tests, used a method of rapidly pressurizing the test components (an impact valve) that significantly exceeded the speed at which a human can open the SCBA handwheel (i.e.,

140 versus 480 milliseconds). This test conservatism was introduced to explore worst case scenario situations, but was not meant to simulate a real world activity.

  • Pre-tes~ temperatures of test articles (i.e., SCBA components) actually reached temperatures as high as 154 degrees Fahrenheit (with no failure evident). NASA post-test inspections revealed "no signs of ignition" (emphasis added) on 0-rings or flexhose.
  • The Lawrence Livermore National Laboratory engineering staff evaluated the potential for incident (safety concern from fire/explosion, etc.) before performing flame testing of the MSA SCBA in question and concluded that

there is no significant hazard increase because of the change from 20% to 35% oxygen."

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