Fire pump are necessary when the water supply in a facility does not generate enough pressure to meet demand for fire sprinklers, standpipes or foam systems. For instance, a high-rise building may have a city water supply that cannot overcome gravity and deliver the pressure required to reach all areas of the structure. Installing a fire pump to boost the water pressure can allow these systems to function properly.
There are many options, styles and arrangements for fire pumps, but they all have one thing in common: They must be engineered and configured to deliver the specific performance requirements for each system. Knowing these requirements ahead of time can help design engineers determine the best fire pump to fit the application and budget.
For example, a hydrant flow test must be conducted to determine the fire pump’s maximum water flow. This data is then used to size the fire pump’s NPSH value and flow capacity. Additionally, the fire pump’s power consumption must be sized to ensure it will not be overloaded when a system activates.
Another important requirement is a fire pump’s horsepower curve, which shows how much power the fire pump will require at different head demands. The curve should peak at the required system head and begin to fall as it nears the rated flow point. Any other point on the curve would indicate that the fire pump is undersized, which is a violation of NFPA 20.
The fire pump’s driver is also an important factor to consider. An electric motor drive is the most popular, as it’s both cost-effective and easy to operate. However, if the facility has a generator back-up, a diesel engine is a great option to ensure the fire pump will work when needed.
It is also vital to note that any fire pump must be inspected, tested and maintained regularly, typically at least once per year. During these tests, a qualified professional will measure the fire pump’s water pressure and flow to make sure that it is functioning as designed. If a fire pump is underperforming, the technician can use this information to fix the issue before it becomes a problem during a real emergency.
As a final consideration, it’s critical to ensure that any fire pump is listed by Underwriters Laboratories (UL) or Factory Mutual (FM). Having these listings means the manufacturer has gone through strict testing to ensure their fire pumps will be able to provide the required performance. This gives peace of mind to facility managers, as they know their fire protection systems will be able to perform when they need them. This is a crucial step in ensuring occupant safety and property protection. In fact, many state codes require that fire pumps be inspected, tested and maintained by a licensed professional. Those who do not follow these guidelines are at risk of fines and even potential shutdown of their entire fire suppression system.