Standard 521, Edition 7
UL 521

Standard for Heat Detectors for Fire Protective Signaling Systems

UL CSDS Proposal Edition 7 Published Date: January 18, 2008 Last Revision: February 28, 2023

Summary of Topics b0521_7_20080118_sum.html

Subject 521

Bulletin Dated: January 18, 2008

SUMMARY OF TOPICS

The following is being proposed for preliminary review and comment only:

1. For Preliminary Review Only: Addition of RTI Value Requirement
Back to Standard 521, Edition 7

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