Scope and Objective
NBC Part 4 addresses three fundamental aspects:
- Fire Prevention: Measures to reduce the likelihood of fire ignition and spread.
- Life Safety: Safe evacuation and rescue of occupants during fire events.
- Fire Protection: Provision of active and passive systems for fire detection, suppression, and containment.
It is applicable to all types of buildings, new or existing, public or private, with categorization based on occupancy type and height.
Classification of Buildings by Occupancy
NBC categorizes buildings into nine groups (Group A to Group I), each having distinct fire safety requirements:
- Group A – Residential
- Group B – Educational
- Group C – Institutional
- Group D – Assembly
- Group E – Business
- Group F – Mercantile
- Group G – Industrial
- Group H – Storage
- Group I – Hazardous
Each group is further sub-classified depending on the nature of use, occupancy load, and fire risk. This classification guides the fire protection features mandated by the code.
Fire Zones and Hazard Classification
NBC mandates the division of cities/towns into Fire Zones (I to IV), based on risk levels due to urban density, building use, and flammable materials. Buildings must comply with the construction standards and material restrictions defined for their respective fire zone.
Additionally, hazard classification (Low, Moderate, High) is applied to industrial buildings to determine fire suppression and compartmentation strategies.
General Requirements and Fire Prevention
NBC prescribes general planning principles such as:
- Minimum setbacks and open spaces for fire appliance access
- Use of non-combustible or fire-retardant materials
- Fire-resistance ratings for structural members
- Avoidance of hazardous service shafts or unprotected vertical openings
Architectural design must ensure fire compartmentation using firewalls and floors with appropriate fire resistance, based on the building’s height and use.
Means of Egress
Means of egress provisions in NBC are critical for life safety and must be independent, unobstructed, and clearly marked. Egress components include:
- Exits (horizontal and vertical): Minimum two per floor
- Staircases and corridors: Fire-protected and smoke-free
- Exit widths: Based on occupant load (not less than 1 m per 50 persons)
- Travel distance to exits: Ranges from 15 m to 45 m depending on occupancy and sprinkler availability
Emergency lighting and signage must ensure visibility during evacuations.
Fire Protection Systems
NBC outlines minimum fire protection systems under four categories:
- Detection & Alarm Systems: Smoke/heat detectors, manual call points, public address systems
- Fire Suppression Systems: Sprinklers, hydrants, standpipes, foam systems
- Smoke Management Systems: Pressurization, ventilation, smoke extraction
- Fire Command Centre: Required for high-rise and complex buildings with centralized monitoring
The level of protection varies by occupancy group, floor area, and height. For instance, automatic sprinklers are mandatory in buildings over 15 m height (except for certain residential occupancies).
Special Provisions
High-rise buildings (above 15 m) and buildings with basements or atriums have additional requirements:
- Fire lifts and refuge areas
- Compartmentation and smoke-proof lobbies
- Emergency power backup for critical systems
- Wet riser systems and fire-fighting shafts
Conclusion
NBC Part 4 provides a detailed, legally enforceable framework for fire and life safety in buildings across India. Compliance with its provisions is not only a statutory obligation but also a foundational responsibility in safe building design and operation. For architects, builders, and fire engineers, early integration of NBC guidelines into planning and execution is critical for mitigating fire risks and ensuring occupant safety
