The most common thread type in use by United States Fire Departments today is National Hose (NH aka NST). Some fire departments have special threaded fire hoses and fire hydrants. Adapters are used in these situations to connect fire equipment with special threads to the standard threads NH.

Female to Male

Female to male fire adapters are typically used to change threads and/or size ranging from garden hose threads (3/4 inches) up to 6 inches. The most common adapters reduce sizes or changes from one thread to another. They are available in aluminum or brass with National Hose (NH), National Pipe Standard Hose (NPSH), Garden Hose Threads (GHT), National Pipe Thread (NPT) and British Pipe Thread (BSP). Aluminum adapters use rocker locks to tighten or loosen - often, in conjunction with a spanner wrench. Brass adapters use rocker lugs, pin lugs, or a hex fitting.

 

 

Female to Female

Female to female fire adapters are often used to connect two adapters or hoses together; or, to connect an additional in-line accessory such as a test gauges or backflow preventers. They are also used frequently to reduce down from a larger connection to a smaller one, on the male outlet(s) of a fire hydrant.

 

 

Male to Male

Male to male fire adapters are used for connecting two different threaded or sized items together. They are particularly useful at connecting Y-valves, in-line Ball valves, and strainers. This is a great way to ensure water will always flow out of the male side of an adapter, which is the preferred method during hose connections.