Scope and Purpose
IS 15105:2002 covers automatic sprinkler systems intended to:
- Detect heat from fire using fusible links or glass bulbs integrated into sprinkler heads.
- Automatically activate water discharge to suppress or control fires.
- Minimize fire spread and damage, protecting occupants and property.
The standard is applicable across various building types, including commercial complexes, warehouses, factories, and high-rise residential buildings.
System Components and Design Criteria
- Sprinkler Heads:
Sprinkler heads are the key discharge components, consisting of a heat-sensitive element that activates at predetermined temperatures (typically 57°C to 93°C). The standard specifies various types of heads such as upright, pendent, and sidewall, each suited for different ceiling layouts and hazards. - Piping Network:
The piping must be constructed of steel or approved corrosion-resistant materials, designed to maintain adequate pressure and flow. The layout ensures even coverage and minimal pressure loss. - Water Supply:
The system requires a reliable water source, either municipal mains, dedicated fire pumps, or storage tanks. IS 15105 mandates sufficient water flow and pressure, typically around 10 liters per minute per square meter of protected area. - Control Valves and Alarms:
Control valves regulate water flow and must be monitored for open/closed status. Alarms linked to valve operation and sprinkler activation provide early warning for emergency response.
Types of Sprinkler Systems
- Wet Pipe Systems:
Pipes are permanently filled with water, allowing immediate water discharge upon sprinkler activation. This system is the most common due to simplicity and reliability. - Dry Pipe Systems:
Pipes are filled with pressurized air or nitrogen and water is admitted only upon activation, used in unheated or freeze-prone areas to prevent pipe freezing. - Deluge Systems:
All sprinklers open simultaneously, releasing water over the entire hazard area, suitable for high-risk processes. - Pre-Action Systems:
Require two-step activation: a fire detection signal opens valves allowing water into pipes, then sprinklers activate individually by heat.
Installation Requirements
- Sprinklers must be positioned to provide full ceiling or area coverage without obstructions.
- Minimum spacing between sprinklers and from walls is strictly regulated to ensure effective spray distribution.
- Sprinkler heads should be installed per manufacturer’s guidelines and IS standards for height and orientation.
Testing and Maintenance
IS 15105 mandates comprehensive testing to verify:
- Hydraulic Performance: Pressure and flow rate at sprinkler heads must meet design parameters.
- Valve Functionality: Control valves should operate reliably and be monitored continuously.
- Alarm Systems: Functional verification of supervisory and fire alarms.
- Physical Inspection: Regular checks for corrosion, obstructions, and mechanical damage.
Routine maintenance includes flushing piping, replacing damaged sprinkler heads, and checking water supply readiness.
Integration and Compliance
Sprinkler systems per IS 15105 are integral to the National Building Code’s fire safety requirements and complement other fire detection and suppression measures. Properly designed sprinkler systems minimize fire spread, reduce damage, and increase occupant safety.
Conclusion
IS 15105:2002 sets stringent criteria for sprinkler systems’ design and operation, ensuring dependable, automatic fire suppression in diverse environments. Adherence to this standard is critical for effective fire risk management in Indian buildings.
