David Bolton Why a Passage Latchset Fails the Fire Door Inspection: The Four Gaps Most Facilities Miss What This Article Covers and Who It Helps A Grade 1 passage latchset looks identical on both sides of a corridor door whether it carries a UL fire label or not. That visual similarity is exactly why p... NFPA 80 cylindrical locks fire door compliance life safety hardware passage latchsets Jul 30, 2026
