Document: NUREG-0800
Document ID: 5f467362-94d3-4914-8c2f-2c2332ad595c
Document Type: srp
Title: ONSITE METEOROLOGICAL MEASUREMENTS PROGRAMS
Source: NUREG-0800
Source URL: https://www.nrc.gov/docs/ML0523/ML052340581.pdf
Revision Date: 2023-06
Chapter: 2
Section ID: 2.3.3
CFR Part: 
CFR Title: 

Content:
s such that the sensors are at least two tower widths away from an open- latticed tower. For temperature sensors, mounting booms need not be as long as those for wind sensors but must be unaffected by thermal radiation from the tower itself. No temperature sensors may be mounted directly on stacks or closed towers. Mounting booms for all sensors should be oriented normal to the prevailing wind at the site. A determination is made whether the terrain at or near the base of the tower will unnaturally affect the wind or temperature measurements. Heat reflection characteristics of the surface underlying the meteorological tower (grass, soil, gravel, paving, etc.) are estimated to assure that localized influences on measurements are minimal. The position, size, and materials used in the construction of the recorder shack and nearby trees are also examined for potential localized influence on the measurements*. (2) General Exposure of Instruments Since the objective of the instrumentation is to provide measure- ments which represent the overall site meteorology without plant structure interference, the tower position(s) must have been selected with this general objective in mind. Examination of topographical maps, which have been modified to show finished plant grade, and a site visit along with professional judgment on airflow patterns are used to determine and evaluate the representativeness of the locations). The plant structure layout including structure heights are examined for potential influence on meteorological measurements. Sensors should be located at least ten obstruction heights away from the obstruction to minimize this influence. b. Meteorological Sensors The type and performance specifications of the sensors are evaluated. Manufacturers' specifications and analysis, and operating experience for these sensors are considered in evaluation of adequacy with respect to accuracy and the potential for acceptable data recovery. Standard- ized evaluations such as