Text

Close-out of National Fire Protection Association Frequently Asked 07-0030 on Establishing Recovery Actions
	ML110070485
Person / Time
Site:	Turkey Point
Issue date:	02/04/2011
From:	Klein A; NRC/NRR/DRA/AFPB
To:	Barrett H; NRC/NRR/DRA
	Barrett, Harold, NRR/DRA, 415-1402
References
	Download: ML110070485 (6)
	v • d • e

February 4, 2011 MEMORANDUM TO: AFPB Files FROM: Alexander R. Klein, Chief /RA/

Fire Protection Branch Division of Risk Assessment Office of Nuclear Reactor Regulation

SUBJECT:

CLOSE-OUT OF NATIONAL FIRE PROTECTION ASSOCIATION FREQUENTLY ASKED 07-0030 ON ESTABLISHING RECOVERY ACTIONS Frequently Asked Question (FAQ) 07-0030 was proposed by National Fire Protection Association (NFPA) 805 transition team at the Turkey Point nuclear plant through the Nuclear Energy Institute (NEI) NFPA 805 Task Force, to clarify the guidance for establishing recovery actions in NEI 04-02, Guidance for Implementing a Risk-Informed, Performance-Based Fire Protection Program under Title 10 of the Code of Federal Regulations (10 CFR) 50.48(c),

Revision 2 (NEI 04-02).

Background

NFPA 805 Section 1.6.52, Recovery Action defines a recovery action as:

Activities to achieve the nuclear safety performance criteria that take place outside the main control room or outside the primary control station(s) for the equipment being operated, including the replacement or modification of components.

NFPA 805 Section 4.2.3.1 states:

One success path of required cables and equipment to achieve and maintain the nuclear safety performance criteria without the use of recovery actions shall be protected by the requirements specified in either 4.2.3.2, 4.2.3.3, or 4.2.3.4, as applicable. Use of recovery actions to demonstrate availability of a success path for the nuclear safety performance criteria automatically shall imply use of the performance-based approach as outlined in 4.2.4.

NFPA 805 Section 4.2.4, Performance-Based Approach states:

When the use of recovery actions has resulted in the use of this approach, the additional risk presented by their use shall be evaluated.

CONTACT: Harold T. Barrett, NRR/DRA (301) 415-1402

AFPB Files 2 NEI 04-02 currently addresses the transition of Operator Manual Actions (OMAs) to recovery actions in the following sections:

4.3.2 Nuclear Safety Performance Criteria

B.2.2.4 Recovery Actions This guidance required clarification with respect to the following:

Differentiation between recovery actions and activities that take place in the main control room or at primary control station(s)

Determination of the population of recovery actions required in the licensees NFPA 805 fire protection program Evaluation of the additional risk presented by the use of recovery actions Evaluation of the feasibility of the recovery actions Evaluation of the reliability of the recovery actions Industry Proposal FAQ 07-0030, Revision 5 proposes adding a five (5) step process to determine recovery actions required for compliance (i.e. determining the population of post-transition recovery actions).

Step 1: Clearly define the primary control station(s) and determine which pre-transition OMAs are taken at primary control station(s) (Activities that occur in the Main Control Room are not considered pre-transition OMAs). Activities that take place at primary control station(s) or in the Main Control Room are not recovery actions, by definition.

Step 2: Determine the population of recovery actions that are required to resolve VFDRs (to meet the risk acceptance criteria or maintain a sufficient level of defense-in-depth).

Step 3: Evaluate the additional risk presented by the use of recovery actions required to demonstrate the availability of a success path Step 4: Evaluate the feasibility of the recovery actions Step 5: Evaluate the reliability of the recovery actions Step 1 incorporates guidance from Regulatory Guide (RG) 1.205, Revision 1, regarding the primary control station and added condition that actions that are necessary to activate or switch over to a primary control station(s) may be considered as taking place at the primary control station(s) under the following conditions:

The actions are limited to those necessary to activate, turn on, power up, transfer control or indication, or otherwise enable the primary control station(s) and make it capable of fulfilling its intended function following a fire.

The actions are feasible and take place in sufficient time to allow the primary control station(s) to be used to perform the intended functions. The intended functions are defined as the original design criteria for the alternative/dedicated shutdown location(s)

AFPB Files 3 as provided in Generic Letter 86-10, Enclosure 2, Question 5.3.10 and Section 5.4.1 of RG 1.189, Revision 2.

The switches or other equipment being operated to transfer control to the primary control station(s) are free from fire damage and the operators are able to travel from the main control room to the transfer location(s) and on to the primary control station(s) without being impeded by the fire.

The actions taken in the process of abandoning a control room and transferring to a primary control station(s) do not meet the definition of a recovery action subject to the conditions above since they are also considered as taking place at the primary control station(s). Conceptually, these actions are part of the primary control station(s) so the additional risk of their use does not need to be evaluated to demonstrate compliance with NFPA 805 Section 4.2.4.

RG 1.205, Revision 1, Section C.2.4 includes a stipulation that the dedicated or alternative shutdown strategy being considered as a primary control station(s) must be previously reviewed and approved by the Nuclear Regulatory Commission (NRC). Licensees may make modifications to their previously approved strategy or propose the use of a new primary control station(s) strategy that has not been previously approved.

If the licensee proposes to make modifications to their previously approved strategy, the licensee must provide a detailed description of the modification to the dedicated or alternative shutdown strategy sufficient for the staff to verify that the strategy meets the attributes provided in Section C.2.4 (electrical independence, command and control, instrumentation, actions necessary to enable (if required), etc.). In addition, licensees should provide sufficient design information to assure that connections/interconnections with safety-related plant systems will not cause a reduction in the capability, redundancy, diversity or design margin for those systems.

If the licensee proposes the use of a new primary control station(s) strategy, there are two options for obtaining NRC staff approval of the new primary control station(s).

Option 1 is to design and install a primary control station(s) in accordance with the guidance and requirements of the existing Fire Protection licensing basis (typically either Appendix R for a pre-1979 plant or NUREG 0800, Chapter 9.5.1, BTP 9.5-1 for a post-1979 plant) and obtain NRC staff approval as part of the NFPA 805 license amendment (note that this process essentially makes a primary control station previously approved by the staff). In accordance with RG 1.205, Revision 1, no delta risk evaluation would be required since the NRC staff will have previously approved the primary control station(s) as part of the NFPA 805 license amendment.

Option 2 is to develop the design and analyze the primary control station(s) using the performance-based approach and provide the necessary evaluation (e.g., fire modeling; fire risk evaluation treating the primary control station as a VFDR with associated delta risk calculation).

The result of this step should be a list of those locations considered to be the primary control station(s) and a list of those activities necessary to enable the primary control station(s).

Step 2 This step determines the population of recovery actions that are required to resolve VFDRs to meet either the risk acceptance criteria or maintain a sufficient level of defense-in-depth.

AFPB Files 4 Step 3 This step evaluates the additional risk of the use of the recovery actions on a fire area basis.

The proposal lists four different processes for this evaluation (the licensee should chose to use one of the four):

Calculate the CDF (and LERF) associated with the VFDR that resulted in the need for the recovery action and then subtracting from that risk the CDF (and LERF) obtained by eliminating the VFDR. This gives the CDF (and LERF) associated with the VFDR and represents the additional risk associated with the use of recovery action in lieu of providing a deterministic resolution.

Model the recovery action explicitly in the Fire PRA with an appropriate human error probability and calculate the CDF (and LERF). Subtract the CDF (and LERF) obtained by eliminating the VFDR in the PRA model to create a compliant case. This gives the CDF and LERF associated with performing the action compared to providing a deterministic solution.

Report the applicable portion of the CDR/LERF (scenario or group of scenarios) for the fire area as a surrogate for the change in risk.

Perform fire modeling in accordance with NFPA 805 Section 4.2.4.1 to demonstrate that the risk of the recovery action compared to deterministic compliance is negligible.

Step 4 This step evaluates the feasibility of recovery actions. The guidance provides a list of 11 feasibility criteria for recovery actions. This list is based on the 9 criteria provided in Appendix B.5.2 of NFPA 805 along with the use of training and drills as originally discussed in earlier versions of NEI 04-02.

Step 5 This step evaluates the reliability of recovery actions. The evaluation of reliability depends upon the method selected to evaluate the risk of recovery actions.

The reliability of recovery actions that are modeled in the Fire PRA should be addressed using Fire PRA methods (i.e., HRA).

The reliability of recovery actions not modeled specifically in the Fire PRA is bounded by the treatment of additional risk associated with the applicable VFDR.

NRC Staff Evaluation

The NRC staff (the staff) has evaluated the FAQ 07-0030, Revision 5 proposal with respect to regulatory compliance and technical adequacy.

AFPB Files 5 The proposed additions to NEI 04-02 are consistent with the regulation and NFPA 805 as well as the guidance provided in Regulatory Guide 1.205, Revision 1. Therefore, the staff finds the proposed changes to NEI 04-02 to be acceptable.

The staff has reviewed the proposed changes to NEI 04-02 as presented in FAQ 07-0030, Revision 5 and finds that nothing in this FAQ would prevent continued endorsement of NEI 04-02. In accordance with RIS 2007-19, the guidance in this FAQ is acceptable for use by licensees in transition. The final endorsement of this FAQ will be addressed by the next revision to Regulatory Guide 1.205.

References:

For details regarding this FAQ, please see the following:

1. FAQ 07-0030, dated January 22, 2009, ADAMS Accession No: ML090290218

2. FAQ 07-0030, Revision 1, dated June 22, 2010, ADAMS Accession No: ML101760219

3. NRC Staff response to FAQ 07-0030, Revision 1, presented at the September 7, 2010 FAQ meeting, ADAMS Accession No: ML102370595

4. FAQ 07-0030, Revision 3, dated September 9, 2010, ADAMS Accession No:

ML102560046

5. FAQ 07-0030, Revision 4, dated September 16, 2010, ADAMS Accession No:

ML102640114

6. NRC staff response to FAQ 07-0030, Revision 4, dated November 4, 2010, ADAMS Accession No: ML103080210

7. FAQ 07-0030, Revision 5, dated November 4, 2010, ADAMS Accession No:

ML103090602

ML090290218