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Standard for Heat Detectors for Fire Protective Signaling Systems

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Standard 521, Edition 7 Edition Date: October 12, 2016
Summary of Topics s0521_7_sum.html

Summary of Topics

This revisions of ANSI/UL 521 is being issued to incorporate the following changes:

1. Alternative Paintbrush Marking for "Do Not Paint" Requirement

2. Updates to Referenced ASTM Standards

Back to Standard 521, Edition 7

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