Fire Rated Steel Door Inspection & Installation Guide

Passive fire protection assemblies compartmentalize thermal energy and smoke, preventing toxic gases from penetrating emergency stairwells. NFPA 80 (Standard for Fire Doors and Other Opening Protectives) mandates strict hardware installation rules and annual 13-point physical inspections.

1. Fire Endurance Ratings & Applications

• 3-Hour Rating (Class A): Installed in firewall openings separating major building structures.
• 1.5-Hour Rating (Class B): Installed in 2-hour rated vertical enclosure shafts, stairwells, and elevator banks.
• 1-Hour Rating (Class C): Installed in room partitions and corridor openings.

2. Key NFPA 80 Gap & Latching Clearance Tolerances

• Clearance Gaps: Top and side leaf-to-frame clearance gaps must not exceed 3.2 mm (1/8 in) for steel fire doors.
• Bottom Clearance: Door leaf bottom to finished floor line clearance must not exceed 19 mm (3/4 in).
• Panic Bar Exit Hardware: Must unlatch under a single forward motion, operating freely without auxiliary locking deadbolts.