EN 1303:2015 Digit 4: Fire Resistance Grade B 90-Minute Assembly Standards
Engineering Overview: Technical specifications for EN 1303:2015 Digit 4 Grade B fire door lock cylinders tested to EN 1634-1 on 90-minute fire barrier assemblies.
Technical & Engineering Specifications
| Material | Solid Extruded H59 Brass or Stainless Steel Only |
|---|---|
| Rating Tier | Grade B (90-Minute Fire & Smoke Door Barrier) |
| Furnace Standard | EN 1634-1 Furnace Test at 1000°C+ |
| Standard Reference | EN 1303:2015 Section 4.5 (Digit 4) |
Fire Containment Compliance
Under EN 1303:2015 Digit 4, lock cylinders installed on fire-rated doors are evaluated for thermal integrity and melting resistance.
Grade B Criteria
- 90-Minute Furnace Endurance: Tested on full door sets under EN 1634-1 at $>1000^\circ\text{C}$.
- Solid Brass Mandate: Zinc components prohibited; body and cam must not melt ($<850^\circ\text{C}$).
Frequently Asked Engineering & Selection Questions
Q1: What does Fire Resistance Grade B mean in EN 1303?
It certifies that the lock cylinder is approved for 90-minute fire and smoke containment doors per European standard EN 1634-1.