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Standard 521, Edition 7

Standard for Heat Detectors for Fire Protective Signaling Systems

UL CSDS Proposal
Standard 521, Edition 7 Edition Date: April 16, 2009
Summary of Topics b0521_7_20090416_sum.html

Subject 521

Bulletin Dated: April 16, 2009

SUMMARY OF TOPICS

The following changes in requirements to the Standard for Heat Detectors for Fire Protective Signaling Systems, UL 521, are being proposed for preliminary review and comment only:

1. For Preliminary Review Only: Clarification of Test Temperature Requirement Details

Back to Standard 521, Edition 7

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