1. Applicable standards: NFPA 20 and ABNT family
Fire protection system design in Brazil follows two references: the international standard NFPA 20 (National Fire Protection Association) and Brazilian ABNT standards. Understanding the scope of each is the first step to correct specification.
- NFPA 20 — International standard for stationary fire pump installation. Defines requirements for main pump, standby, jockey, controllers and testing
- NBR 10897 — Fire protection by automatic sprinkler. Defines flow and pressure at nozzles
- NBR 13714 — Hydrant and hose reel systems for fire fighting
- NBR 16704 — Stationary pumps for fire protection. Brazilian standard specific to the pumps (the "Brazilian NFPA 20")
2. The three system pumps: main, standby and jockey
NFPA 20 requires redundancy. The complete system has three pumps with distinct functions:
| Pump | Drive | Function | When it operates |
|---|---|---|---|
| Main | Electric motor | Provides flow and pressure to the sprinkler and/or hydrant system | Auto-start on network pressure drop |
| Standby (diesel) | Diesel engine | Takes over during power failure or main pump failure | Auto or manual start. Diesel tank autonomy per standard |
| Jockey | Electric motor (smaller) | Maintains constant network pressure. Compensates leaks and variations | Operates continuously at low flow. Prevents unnecessary main pump starts |
3. Main pump — FBCN for fire systems
FB Bombas uses the FBCN series (normalized centrifugal) as the main pump in fire pump systems. The FBCN meets NFPA 20 and NBR 16704 requirements with the following characteristics:
- Flow: sized per system demand (sprinklers + hydrants + reserve)
- Pressure: per building height + friction losses + minimum pressure at the most remote nozzle
- Back-pull-out construction: maintenance without disconnecting piping (essential for system availability)
- Materials: cast iron (standard) or steel for saltwater or additive applications
- Speed: up to 3,500 rpm per FBCN manual
4. Pre-assembled skid: what it includes
FB Bombas supplies the complete system pre-assembled on a metal skid, ready for on-site installation. The typical scope includes:
- Main pump (electric motor) sized for the project
- Standby pump (diesel engine) with fuel tank and starting battery
- Jockey pump for continuous pressurization
- Automatic control panel (pressure switch start, alarms, monitoring)
- Gate, check, relief and test valves
- Suction and discharge manifolds with flanges
- Structural metal base with leveling feet
5. The curve the standard demands — and the tests that prove it
A fire pump is not an ordinary centrifugal pump painted red — NFPA 20 imposes a specific curve shape. The pump must deliver 150% of rated flow at no less than 65% of rated pressure, and shut-off pressure (zero flow) cannot exceed 140% of rated. This geometry guarantees two things at once: real capacity reserve when the fire opens more hydrants or sprinklers than the design assumed, and protection of the network against overpressure when demand drops.
Proof happens at two moments. At the FAT (factory acceptance test), the pump runs on the test bench with calibrated measurement at the three curve points — shut-off, 100% and 150% of rated flow. At field commissioning, the test is repeated on the real installation, with the definitive suction system and electric or diesel supply. Specifying without requiring both documented tests means giving up the only objective evidence that the system delivers what the hydraulic design calculated.
6. Specification mistakes that cost system approval
The most expensive problems surface at the Fire Department inspection or the insurer audit — when fixing means construction work. Four mistakes account for most rejections:
- Specifying an ordinary centrifugal pump instead of one with an NFPA 20-compliant curve — it meets rated flow and pressure but fails the curve-shape requirement
- Entrusting backup to a generator shared with other building loads — without NFPA 110 Level 1 qualification, the correct alternative is a dedicated diesel-driven pump
- Omitting the jockey pump — the main pump starts on every small pressure drop, accumulating cycles that neither the standard nor the set's service life tolerates
- Treating documentation as bureaucracy — without certified curve, data book and test records, approval stalls even with a physically correct system
7. Where it applies: building types and industries
Fire pump systems are required by law or insurers across various building categories and industrial facilities:
- Shopping centers, hospitals and condominiums — sprinklers + hydrants per NBR 10897 and NBR 13714
- Logistics warehouses and storage facilities — areas with high fire load
- Refineries, power plants and fuel terminals — NFPA 20 requirement by risk class
- Sugar-ethanol mills — combustible bagasse + flammable ethanol
- Pulp and paper mills — fibrous materials and boilers
