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Standard for Heat Detectors for Fire Protective Signaling Systems

UL CSDS Proposal
Standard 521, Edition 7 Edition Date: January 18, 2008
Summary of Topics b0521_7_20080118_sum.html

Subject 521

Bulletin Dated: January 18, 2008


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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