Document: NUREG-0800
Document ID: 63521156-eb6b-472c-9560-1e85462dc1be
Document Type: srp
Title: ENVIRONMENTAL QUALIFICATION OF MECHANICAL AND ELECTRICAL
Source: NUREG-0800
Source URL: https://www.nrc.gov/docs/ML0520/ML052070288.pdf
Revision Date: 2023-06
Chapter: 3
Section ID: 3.11
CFR Part: 
CFR Title: 

Content:
fy nonmetallic material capabilities; and (5) evaluate environmental effects.104 D. MILD ENVIRONMENT (1) The environmental qualification of all electrical and mechanical equipment located in thea mild environment is acceptable if the following procedure is 105 followed: 106 (a) The documentation documents required to demonstrate qualification of 107 equipment in a mild environment are the "Design/Purchase" specifications. The specifications shall contain a description of the functional requirements for itsa specific environmental zone during normal and abnormal environmental conditions and anticipated operational occurrences. A well-supported maintenance/surveillance 108 program in conjunction with a good preventive maintenance program will suffice to assure ensure that equipment that meets the design/purchase 109 specifications is qualified for the designed life. (b) Furthermore, the maintenance/surveillance program data and records 110 shall be reviewed periodically (not more than 18 months) to ensure that the design qualified life has not suffered thermal and cyclic degradation resulting from the accumulated stresses triggered by the abnormal environmental conditionsanticipated operational occurrences and the 111 normal wear due to its service condition. Engineering judgment shall be used to modify the replacement program and/or replace the equipment as deemed necessary. E. The potentially adverse effects of inadvertent condensate formation in, and/or freezing of, safety related instrument sensing lines which could prevent the affected instrumentation from performing its intended safety function, should be considered as part of the design and arrangement. The reviewer should identify any safety related sensing lines which are relying on heat tracing and/or room heating for prevention of possible freezing and assure that adequate redundancy and other appropriate measures have been implemented, to preclude inadvertent effects caused by adverse conditions. The