IS 1644:2011 is the Indian Standard (BIS) for fire safety of buildings - general: air conditioning - code of practice. This code specifies the fire safety requirements for the design, installation, and maintenance of air conditioning and ventilation systems in buildings. It aims to prevent the spread of fire and toxic smoke through HVAC ductwork by mandating the use of fire dampers, non-combustible materials, proper fire stopping, and automatic AHU shutdown mechanisms.
Lays down provisions for fire safety of air conditioning systems in buildings, including design, installation, and operation.
Overview
- Status
- Current
- Usage level
- Frequently Used
- Domain
- Fire Safety — HVAC and Air Conditioning
- Type
- Code of Practice
Also on InfraLens for IS 1644
BIM-relevant code. See the BIM Hub for ISO 19650, IFC, and LOD/LOIN frameworks used alongside it.
Practical Notes
! Ensure adequate access doors are provided near fire dampers for periodic inspection and manual resetting.
! Ductwork penetrating fire-rated walls must be properly fire-stopped around the perimeter to maintain the compartment's integrity.
! Never use combustible materials for duct acoustic lining or external thermal insulation.
Frequently referenced clauses
sheet metalinsulationfire dampersfire stopping sealants
International Equivalents
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International Comparison — Coming Soon
We're adding equivalent international standards for this code.
Key Values4
Quick Reference Values
fire damper ratingMinimum 90 to 120 minutes matching the penetrated fire barrier
AHU shutdown mechanismAutomatic via smoke detectors in the return air stream
duct clearance gapFilled with approved fire-stopping material
insulation flammabilityStrictly non-combustible
Tables & Referenced Sections
Key Tables
Table 1 - Fire Resistance Ratings for Fire Dampers based on Compartment
Key Clauses
Clause 4 - Requirements for Air Conditioning Systems
Clause 5 - Installation of Fire Dampers
Clause 6 - AHU Room Layout and Fire Separation
Clause 7 - Smoke Extraction and Ventilation
Clause 8 - Duct Material and Insulation
Frequently Asked Questions3
When are fire dampers mandatory in ductwork?+
Fire dampers must be installed wherever an air duct penetrates a designated fire compartment wall, floor, or fire-rated partition.
What happens to the HVAC system upon fire detection?+
The Air Handling Units (AHUs) must automatically trip to prevent the recirculation of smoke into other building zones.
Can AHU rooms be used for general storage?+
No, AHU rooms must be dedicated strictly to HVAC equipment and kept entirely free of combustible storage.
QA/QC Inspection Templates
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QA/QC templates coming soon for this code.