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Standard for Heat Detectors for Fire Protective Signaling Systems

UL CSDS Proposal
Standard 521, Edition 7 Edition Date: October 27, 2017
Summary of Topics b0521_7_20171027_sum.html

Subject 521

Bulletin Dated: October 27, 2017


The following changes in requirements to the Standard for Safety for Heat Detectors for Fire Protective Signaling Systems, UL 521, are being proposed:

1. Graph Modification for Fire Test Temperature Profile

Back to Standard 521, Edition 7

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