When installing a Combustible Gas Detection System (in industrial establishments with restricted public access, and using qualified personnel to service the installation) as a protection technique in a Class I hazardous (classified) location of Article 501, or a Zone location of Article 505, all but which of the following items shall be documented?

A) Purchase date / installation date
B) Calibration frequency
C) Alarm and shutdown criteria
D) Installation location
E) Type of detection equipment and its installation listing

Answer: A

Explanation: Per a 2005 change, 500.7(K) and 505.8(I) were revised to make it clear that (1) the type of detection equipment, (2) the listing of detection equipment, (3) the installation location(s) of detectors, (4) shutdown criteria, and (5) calibration frequency shall be documented when combustible gas detectors are used as a protection technique. Documentation of purchase date / installation date is not required.

Owen is the owner and president of National Code Seminars and the holder of master electrician certifications in 46 states. He can be reached at necexpert@aol.com.