This code establishes guidelines to prevent the spread of fire between adjacent buildings (exposure hazard), primarily focusing on radiant heat transfer and flying embers. It provides methods to determine safe separation distances based on the building's fire load, the dimensions of the radiating face, and the percentage of unprotected openings.
Code of practice for fire safety of buildings (general): Exposure hazard
Quick Reference Values
acceptable radiation intensity limit12.5 kW/m² (0.3 cal/cm²/sec) for ignition of wood
low fire load limitNot exceeding 2.75 x 10^5 kcal/m²
moderate fire load range2.75 x 10^5 to 5.5 x 10^5 kcal/m²
high fire load limitExceeding 5.5 x 10^5 kcal/m²
Key Formulas
Configuration factor / Safe distance calculations based on radiant heat intensity and unprotected percentage of building face.
Practical Notes
Always cross-reference with the latest National Building Code (NBC Part 4), as local fire bylaws often supersede or integrate these guidelines.
When calculating safe separation distances, treat ordinary glass windows and non-fire-rated doors as 100% unprotected openings.
Parapet walls and fire-resistant roof coverings are critical in mitigating fire spread from flying brands (embers).