Document: NUREG-0800
Document ID: 31337ac3-66c6-42b1-b9e0-1655cad200d1
Document Type: srp
Title: ONSITE METEOROLOGICAL MEASUREMENTS PROGRAMS
Source: NUREG-0800
Source URL: https://www.nrc.gov/docs/ML0520/ML052070232.pdf
Revision Date: 2023-06
Chapter: 2
Section ID: 2.3.3
CFR Part: 
CFR Title: 

Content:
he frequency of attention that the instrumentation systems receive are compared to operating experience at this site and other sites with similar instrumentation with the objective of determining that acceptable data recovery with acceptable accuracy will be obtained throughout the duration of the meteorological program. The ability of instrumentation systems to function throughout the course of accidents is evaluated. Criteria for 27 acceptable accuracy and acceptable data recovery are specified in Regulatory Guide 1.23, Positions C.4 and C.5. e. Data Acquisition and Reduction The procedures, including both hardware and software for data acquisition and reduction, are evaluated. Since there are many methods of acquiring data from meteorological measurement systems which are acceptable to the staff, the review procedure varies. The basic components of the program which are reviewed to ascertain the acceptability of data acquisition and reduction are: (1) Accuracy of direct measurements and their precision, (2) Accuracy in conversion of direct measurement units to meteorological units, (3) Adequacy of frequency and mode (instantaneous or average) of sampling, and (4) Averaging time of system outputs for final disposition and accuracy of these data. Since the instrument accuracy criteria in Regulatory Guide 1.23 refer to overall system accuracy for time-averaged values, the overall system accuracy is evaluated in addition to the component (sensor, recorder, and reduction) accuracies. The evaluation consists primarily of using statistical procedures for compound errors, based on sensor accuracy, recorder accuracy, conversion of units accuracy, and frequency and mode of sampling (Reference 10). 2. Meteorological Data Summaries Annual (i.e., representing the annual cycle) joint frequency distributions of wind direction and wind speed by atmospheric stability class are evaluated for sufficient detail to permit the staff to make an independent determination of the