Fire pumps are critical components in many building fire protection systems, ensuring adequate water pressure is available when sprinklers or standpipes activate. But what happens if the main power source fails during a fire? This leads to a crucial question: Does a fire pump require emergency power?
The answer depends on several factors—building occupancy, local code requirements, the type of fire pump, and whether your fire protection strategy can maintain performance without power interruptions. This article will break down the requirements, standards, and options for providing emergency power to fire pumps, drawing from NFPA 20 guidelines and practical engineering considerations.
Fire pumps can be powered in three main ways:
Electric Motor-Driven Fire Pumps – The most common type in commercial buildings. They require a reliable power source and may need backup power if code mandates it.
Diesel Engine-Driven Fire Pumps – Operate independently of the building’s electrical supply, often used where electrical reliability is a concern.
Steam Turbine-Driven Fire Pumps – Rare today, but still possible in facilities with steam infrastructure.
Electric pumps are efficient, but they rely on electrical supply—making them vulnerable to outages unless an emergency power system is in place. Diesel-driven pumps, on the other hand, can bypass this vulnerability but have their own maintenance requirements.
NFPA 20: Standard for the Installation of Stationary Pumps for Fire Protection provides the main reference for fire pump installation in the U.S. and internationally where adopted.
According to NFPA 20:
Emergency power is not always mandatory for fire pumps.
Instead, NFPA 20 focuses on ensuring a reliable power source.
A “reliable” source may mean a utility connection with a strong track record of uptime, or it could mean having a backup generator or alternate power method.
Key points from NFPA 20:
If the electrical service to the pump is not deemed reliable, an alternate source of power (such as a generator or diesel pump) must be provided.
Reliability is often defined by the Authority Having Jurisdiction (AHJ), based on historical outage data, infrastructure, and environmental conditions.
High-rise buildings, hospitals, and critical facilities are more likely to be required to provide emergency power due to life safety priorities.
While NFPA 20 doesn’t impose a universal requirement, emergency power for fire pumps is often mandated in:
High-rise buildings – Power outages during fires are a significant risk, and redundancy is critical.
Hospitals and health care facilities – Patient safety demands uninterrupted fire protection.
Critical infrastructure – Airports, data centers, military installations, and large industrial facilities often have backup requirements.
Municipal requirements – Some cities have stricter codes than NFPA 20, making emergency power mandatory for most commercial fire pumps.
Local building codes, such as the International Building Code (IBC) or NFPA 101 Life Safety Code, may also specify emergency power needs, sometimes going beyond NFPA 20’s baseline requirements.
If an emergency power supply is required or deemed necessary for operational safety, there are several options:
How they work: Automatically start when utility power is lost, supplying electricity to the fire pump.
Advantages: Can power other life safety systems like lighting, alarms, and elevators.
Considerations: Must be sized to handle the large inrush current of electric fire pump motors; installation cost is significant.
How they work: Operate independently using diesel fuel stored onsite.
Advantages: No need for a generator; direct mechanical drive.
Considerations: Require regular maintenance, fuel storage, and ventilation systems.
How they work: Fire pump is supplied by two separate utility lines, each from different substations.
Advantages: Reduces generator needs.
Considerations: True independence of utility feeds must be verified; still vulnerable to wide-area outages.
Rare today, but viable in facilities with steam power infrastructure.
Providing emergency power is not only about meeting code—it’s about ensuring your fire protection system functions when needed most. The decision should weigh:
Historical outage data for your facility’s location.
Criticality of operations—loss of fire protection could have devastating safety or financial consequences.
Installation and operating costs of emergency power solutions.
Regulatory compliance with local and national codes.
For example, an industrial facility in a hurricane-prone area might opt for a diesel pump to ensure functionality during prolonged outages, while a downtown high-rise may rely on a generator system tied to the building’s life safety power.
Even when emergency power is installed, mistakes can undermine reliability:
Undersized generators – Electric fire pump motors require high starting current; undersizing causes voltage drops and pump failure.
Lack of dedicated transfer switches – Fire pumps require a transfer switch specifically rated for motor loads.
Neglecting maintenance – Both diesel pumps and generators must be tested under load regularly to ensure readiness.
Improper fuel storage – Diesel pumps must have adequate, safely stored fuel for at least the minimum operational duration required by code.
If you are installing or upgrading a fire pump system, follow these best practices:
Engage with the AHJ early to determine if emergency power is mandatory.
Document reliability of your primary power source to avoid costly retrofits.
Choose equipment with proven performance and compliance with NFPA 20 and local regulations.
Schedule routine maintenance and testing for generators, diesel pumps, and transfer equipment.
Consider redundancy beyond code minimums—especially in mission-critical facilities.
So, does a fire pump require emergency power?
Not always by NFPA 20, but in many cases—especially in high-risk or high-occupancy facilities—yes.
The key is to ensure a reliable, uninterrupted power supply so your fire pump can operate during the worst-case scenario.
Whether that means installing a generator, selecting a diesel engine pump, or securing dual utility feeds, the decision should be guided by code requirements, risk assessment, and operational priorities.
A fire pump is only as good as the power driving it—ensuring that power is available at all times is a cornerstone of effective fire protection.
