U.S. Nuclear Regulatory Commission
Clarification of the 11 Criteria of NUREG-0737 on Postaccident Sampling System
HPPOS-011 PDR-9111210103
Title: Clarification of the 11 Criteria of NUREG-0737 on
Postaccident Sampling System (PASS) Capability
See the letter from S. A. Varga to J. A. Jones (Vice
President, Carolina Power and Light Company) dated
September 24, 1982. Enclosed with this letter were the 11
criteria contained in NUREG-0737, Item II.B.3, on PASS
capability and clarification developed by the NRR staff.
These 11 criteria are briefly discussed below; however, the
document must be reviewed in its entirety. The licensee
must:
1. Provide information on sampling and analytical
laboratory locations and their relative elevations,
distances, as well as sample handling, transport,
recirculation, analytical time limits, and provisions for
sampling during loss of off-site power sufficient to meet a
3-hour sampling and analysis time limit.
2. Provide discussions of counting equipment
capabilities including provisions for sample handling and
background radiation reduction to personnel (ALARA);
procedures relating radionuclide concentrations to reactor
core damage including the monitoring for short and long
lived volatile and nonvolatile radionuclides, as well as
provisions for estimating core damage based on radionuclide
concentrations, core temperatures and sample location;
discuss the capability of obtaining a grab sample,
transport and analyzing for hydrogen; discuss capabilities
to sample and analyze for accident sample species; and
discuss the suitability, reliability and maintenance
information of selected on-line instruments.
3. Provide system schematics and discussions that
clearly demonstrate PASS, including recirculation, is
possible without using isolated auxiliary systems.
4. Discuss methodologies for measuring total dissolved
gas or hydrogen and oxygen and how this information is
related to reactor coolant system concentrations. In
addition, if chlorides exceed 0.15 ppm, verification that
dissolved oxygen is <0.1 ppm is required.
5. BWR's located near or using sea or brackish water
in heat exchangers with single barrier protection are
required to analyze chloride within 24 hours. All other
plants have 96 hours. Initial chloride analysis must use
dilutions of <1:1000, be reported in units of ppm, and have
<0.1 ppm dissolved oxygen.
6. Provide information on predicted personnel
exposures based on person-motion sampling, transport and
analysis of samples.
7. PWR's must perform boron analysis on primary
coolant. BWR's must have the capability to perform boron
analysis, but need not do them providing boron was not
injected.
8. Have the capability to obtain diluted and undiluted
backup samples when required. If off-site laboratories
will do the backup analysis, an explanation of the
capability to obtain and ship one sample per week until
accident conditions do not exist is needed.
9. Discuss the predicted activity in the samples to be
taken and the methods of handling / dilution used to reduce
activity sufficiently for the required analysis. The
predicted background radiation levels in the counting room,
including the contribution from other samples, must be
stated. 10. Discuss the accuracy, range, and
sensitivity of the methods of analysis. These must be
adequate to provide the operator sufficient and pertinent
data describing the radiological and chemical status of the
reactor coolant system. The recommended accuracy,
sensitivity, and ranges for numerous compounds are
described in this criterion.
11. Describe provisions for purging sample lines,
reducing sample line plateout, decreasing sample loss and
distortion, preventing sample line blockage, sample
disposal, and limiting reactor coolant loss from ruptured
sample lines. The ventilated exhaust from the sampling
station must be filtered with charcoal absorbers and HEPA
filters, however, the ventilation system need not be
dedicated.
Regulatory references: NUREG-0737, Technical Specifications
Subject codes: 5.0, 7.6, 8.3, 10.1, 12.16
Applicability: Reactors
