FIRE SAFETY IN HVAC SYSTEMS

(As per NBC 2016 / NFPA 90A / ASHRAE 15)

1. Fire Dampers

Installed at wall/floor duct openings
Close automatically in fire
Stop fire spread between rooms

2. Smoke Dampers

Control movement of smoke
Operate through fire alarm system (FAS)
Help keep escape paths clear

3. Combo Dampers

Work for both fire + smoke
Used in important areas
Automatic operation

4. AHU Interlocking

AHU stops during fire
Connected with fire alarm
Prevents smoke circulation

5. Staircase Pressurization

Keeps staircase smoke-free
Maintains positive pressure
Helps safe evacuation

6. Smoke Extraction

Removes smoke from building
Used in basement / large areas
Starts automatically in fire

7. Duct Fire Safety

Metal ducts (non-combustible)
Fire-rated if required
Limits smoke & fire spread

Key Point

HVAC should not spread fire or smoke
All systems must work automatically

Simple Understanding:

HVAC in fire = Stop Smoke + Safe Escape

Comments

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