Fire Protection Systems for Industrial Plants
How to size the fire water reserve for an industrial plant to NFPA 22 using turn-key bolted steel tanks, plus data-backed design parameters.
A fire protection system for an industrial plant is designed around a dedicated, exclusive water reserve: a volume that guarantees flow and pressure to the suppression systems (hydrants, sprinklers, monitors) for the required duration, even if the external supply fails. At Tech Tank we deliver that storage with bolted steel tanks sized to NFPA 22, with the reserve volume calculated from the fire demand (GPM) and the design duration. It is a turn-key solution: calculation, tank, fittings and commissioning.
The sector challenge: water available when the process fails
An industrial plant concentrates fire risks (fuels, thermal processes, storage, electrical lines) and cannot rely on the public water main, which usually delivers unstable or insufficient pressure and flow for a fire event. Insurance standards and good practice demand a private, untouchable reserve: fire water must never be shared with process consumption because it has to be 100% available at all times.
The technical challenge has three parts:
- The right volume: neither too little (loss of life and total loss) nor too much (over-cost and wasted space).
- Permanent availability: the reserve level must be protected by stepped take-offs or independent lines, so daily consumption never draws down the fire volume.
- Structural and sanitary reliability: the tank must resist corrosion for decades and keep the water in condition, with straightforward inspections.
The Tech Tank solution: dedicated reserve to NFPA 22
NFPA 22 (Standard for Water Tanks for Private Fire Protection) is the international reference for fire protection water tanks. It defines materials, fittings, connections, protection of the reserve volume and nameplate requirements. Our bolted steel tanks meet those requirements and are combined with the hydraulic design of the installation (sprinkler system to NFPA 13 and hydrant mains to NFPA 24) to set the volume and connections.
Why bolted steel? Compared with cast-in-place concrete or field-welded steel, a bolted steel tank with glass-fused-to-steel (GFS) coating is factory-manufactured, shipped disassembled and erected on site in a matter of weeks. The vitreous coating is never repainted, resists the corrosion of standing water (the normal condition of a fire tank) and offers a service life on the order of 30 to 50 years with minimal maintenance. For the technology in detail, see what a bolted steel tank is.
How the reserve volume is calculated
The fire volume comes from multiplying the demand flow by the design duration, adding hose demand where applicable:
Volume = (Sprinkler flow + Hose flow) × Duration
Illustrative example: a combined demand of 2,400 L/min sustained for 90 minutes requires about 216 m³ of reserve. A higher hazard (high-piled storage, flammable liquids) may demand 120 minutes or much higher flows. Typical duration by hazard class ranges from 30 to 120 minutes. The final figure is set by the fire protection engineer; we provide the tank that materializes that number. For the general logic of sizing water reserves, see how to size a water storage tank.
Data-backed benefits
- Fast erection: a bolted tank is raised in weeks, not months. It shortens the time until the plant is protected and insurable.
- Long service life: GFS coating compliant with ISO 28765, never repainted, with a service life on the order of 30 to 50 years.
- Protected reserve: connections and take-offs arranged so service consumption never invades the fire volume (anti-vortex, nameplate and venting per NFPA 22).
- Expandable and relocatable: being modular, it can be disassembled, raised in height or moved if the plant layout changes.
- Easy inspection: standardized access, ladder and fittings ease the periodic inspections required by insurers and fire authorities.
Typical design parameters
| Parameter | Typical range | Reference |
|---|---|---|
| Reserve duration | 30 – 120 min | By hazard classification |
| Reserve volume | 50 – 2,000+ m³ | NFPA 22 / hydraulic demand |
| Demand flow | 1,000 – 6,000+ L/min | NFPA 13 (sprinklers) + NFPA 24 |
| Tank coating | Glass-fused-to-steel (GFS) | ISO 28765 / AWWA D103 |
| Estimated service life | 30 – 50 years | With minimal maintenance |
| Erection time | 2 – 6 weeks | By capacity and site |
Values are indicative: the final figure depends on the fire protection design, the occupancy classification and applicable local regulations.
Integration with the plant
The tank does not work alone. A complete system combines the water reserve with the fire pump house (main pump, jockey and, where required, diesel backup), the distribution network, hydrants and sprinklers. As a turn-key integrator, we coordinate the tank with the rest of the system so that connections, suction level and reserve protection are consistent with the hydraulic design. See the approach behind our fire protection system solutions.
If you are defining fire protection for a new plant or expanding an existing one, contact us to quote the tank and its sizing: we start from your hydraulic demand and design duration to propose the correct reserve.
Frequently Asked Questions
Which standard governs a fire water tank?
The international reference standard is NFPA 22 (Standard for Water Tanks for Private Fire Protection), which defines materials, fittings and protection of the reserve volume. It is complemented by NFPA 13 (sprinklers) and NFPA 24 (private hydrant mains) to set the flow. In Paraguay you should also verify local fire authority and insurer requirements.
Can I use the same tank for process water and fire water?
Only if the fire volume is physically protected. This is achieved with stepped take-offs: the service line draws above the reserve level, so daily consumption can never lower the water reserved for fire. Even so, for critical installations a dedicated reserve is recommended.
How much reserve volume do I need?
It depends on the demand flow and the design duration. It is calculated by multiplying the flow (sprinklers plus hoses) by the time, typically between 30 and 120 minutes depending on hazard. A common moderate-risk case is around 100 to 300 m³, but a flammable-liquid storage area can require much more.
Why bolted steel and not concrete?
Bolted steel with vitreous coating is factory-made and erected in weeks, does not crack like concrete, needs no repainting and offers 30 to 50 years of service life. It is also modular: it can be expanded, disassembled or relocated if the plant layout changes.
Does the tank include the fire pumps?
The tank is the water reserve. As a turn-key integrator we coordinate the tank with the pump house (main, jockey and backup), the network and the fittings, but the exact scope is defined per project. What matters is that the suction level and reserve protection are consistent with the hydraulic design.