- Fire Protection System Definition: A fire protection system in power plants includes devices and protocols to detect and extinguish fires, often involving hydrants, sprays, and foam technologies.
- Regulatory Compliance: Fire protection setups must comply with TAC or NFPA standards to ensure safety and insurance benefits.
- Water Reservoir and Pumps: Essential components like fire water reservoirs and dual-source pump systems form the backbone of a fire suppression system.
- Fire Suppression System: Central to fire safety, this system includes various technologies to effectively control and extinguish fires in power plants.
- Safety and Maintenance: Regular checks and maintenance of fire protection equipment are crucial for operational reliability and effectiveness.
A power-plant fire protection system is the water supply, detection and extinguishing plant that finds and fights fire on a generating station. Adding megawatts without that plant raises loss and injury risk.
Thermal Power Plants in India are often classed as ordinary hazard occupancy by the Tariff Advisory Committee (TAC). Design of the complete fire protection system on an Indian insured plant is written to TAC rules. Where TAC is silent, NFPA 850 (electric generating plants) and the related NFPA 15 (water spray) and NFPA 20 (fire pumps) documents are the usual international references. TAC or successor approval is what lets an Indian owner claim the insurance rebate those rules describe. Plants outside that scheme follow the authority having jurisdiction, not TAC by default.
Thermal Power Plants combine boilers, turbines, transformers, oil systems and coal handling. Hot surfaces, lubricating oil and coal dust are the usual fire loads. This part lists the water-supply and pump elements of a Fire Protection System.
The main blocks of that system are:
Fire Water Reservoir or Fire water Pump House
The fire-water pump house supplies the fire protection system. On a TAC-insured Indian plant the pump set is laid out to TAC. NFPA 20 is the usual international fire-pump standard. A storage tank holds water for fire service. Pumps start automatically from pressure switches. Stopping remains manual so a falling pressure cannot shut a pump that is still needed.
Fill water for that tank is taken from two independent sources on this specification:
- From the raw-water pump discharge header.
- From circulating-water blowdown.
This specification splits the tank into two equal compartments with isolation valves between them. Each compartment feeds a common suction header so any pump can take suction from either side, matching TAC practice. At least two discharge headers leave the pump house and are looped around the risks. Isolation valves let a damaged length be taken out without draining the whole ring.
Pumps Installed in Fire Water Pump House
Hydrant and spray duties have their own fire-water pumps. A valved blank is left on the network for later extension. Capacity and head are sized to the hydraulics and, on an Indian insured plant, to TAC. NFPA 20 sizes pumps to the hydraulically most remote demand plus the code residual pressure, which can differ from TAC.
This contract data sheet lists these machines in the fire-water pump house:
- Electric motor driven main fire-water pump.
- Diesel-engine driven fire pumps (standby to the electric set).
- Each diesel pump has 2 × 100% battery chargers and batteries for starting.
- Electric jockey pumps that hold ring-main pressure (one duty, one standby).
- Air compressor for the hydro-pneumatic tank that keeps the ring primed.
Fire Water Pumps Data Sheet
Rated capacity, speed and materials on this data sheet are:
| S.No. | Description | Electric Motor driven pump | Diesel engine driven pump | Jockey pump |
| 1.0 | General Information | |||
| 1.1 | Rated Capacity/Nos | Contractor to decide (minimum 3 nos.) for hydrant MVWS system and minimum 1 no for HVWS system | Contractor to decide (minimum 2 nos. for hydrant MVWS system and minimum 1 no for HVWS system) | Contractor to decide |
| 1.2 | Rated speed (rpm) | 1500 | 1500 | 2900 |
| 1.3 | Total head at the pump discharge MWC | As per system requirement | As per system requirement | As per system requirement |
| 1.4 | TAC approval required | yes | yes | yes |
| 1.5 | Used for service like | Hydrant and spray system | Hydrant and spray system | Common for Hydrant and spray system |
| 2.0 | Material of construction | |||
| 2.1 | Casing | SS304 | SS304 | SS304 |
| 2.2 | Impeller | Stainless steel | Stainless steel | Stainless steel |
| 2.3 | Shaft | Stainless steel | Stainless steel | Stainless steel |
Control and operating philosophy
The ring main is kept pressurised so a pressure drop starts the fire pumps automatically. How hydrant, spray, foam and booster pumps sequence is described in Parts II and III of this series.
- Hydrant and MVWSS
- Hydrant and HVWSS
- Fixed Foam system
- Fire water booster pump
Constructional requirements
- Hydrant, spray and foam mains on this spec run above ground on concrete pedestals.
- In the main plant and coal yard, this spec puts pipes in sand-filled RCC trenches with removable covers. Road and rail crossings use Hume pipes.
- Fire-water pipe on this Indian spec is carbon steel to IS 1239 (medium) and IS 3589. Other jurisdictions use their own pipe standards.
- Above-ground pipe is supported on concrete pedestals at intervals set by the piping stress check.
- Buried pipe is double-coated and wrapped to IS 10221 or IS 15337 on this spec.
- This spec limits water velocity in any section to 5.0 m/s. NFPA water-spray piping may use a different velocity cap; size the pipe to the adopted code.
- Pump pressure is set so the remotest and highest hydrant still meets TAC residual pressure on an Indian insured plant.
- Hose cabinets on this spec are 16 SWG with 3 mm glass, a lock-box and a pedestal. Hose is IS 636 Type A.
Hydrant System
(covered in part II of this series)
Spray System
(covered in part II of this series)
Fix Foam system
(covered in part III of this series)
Potable and mobile extinguisher
(covered in part III of this series)
