Standard 521, Edition 7
UL 521

Standard for Heat Detectors for Fire Protective Signaling Systems

UL CSDS Proposal Edition 7 Published Date: January 30, 2015 Last Revision: February 28, 2023

Summary of Topics b0521_7_20150130_sum.html

Subject 521

Bulletin Dated: January 30, 2015

SUMMARY OF TOPICS

The following is being proposed:

1. Reaffirmation and Continuance of the Seventh Edition of the Standard for Heat Detectors for Fire Protective Signaling Systems, UL 521, as an American National Standard.
Back to Standard 521, Edition 7

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