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Home Fire Hydrants What is a Fire Hydrant?

What is a Fire Hydrant?

Fire Hydrants are used to supply the operational fire ground with a continuous supply of water in the event of an emergency. These are called statutory Fire Hydrants

Hydrants are connected to the water main, and they are installed in underground chambers, situated below pit covers which are typically painted yellow.  The covers are usually marked FH, but they may have other markings such as WO.

A pit cover for a hydrant, painted yellow with FH painted on it
A pit cover for a hydrant, painted yellow but this has WO painted on it

Hydrants are identified and located by yellow marker plates which are usually positioned to face the direction of the hydrant although they may include an arrow to indicate the direction to the hydrant.  The plates may be fixed to walls, fences, street furniture such as lamp posts or they may be fixed to short posts made of either concrete or fibreglass. 

The marker plates consist of a letter ‘H’ and two numbers.  The top number indicates the diameter of the water main and the bottom number indicates the distance to the hydrant from the plate.  This figure is usually in metres but older markers may quote main size in inches and the distance to the hydrant in feet.

The yellow marker plate on a post with the letter H and two numbers - 75 and 5
The yellow marker plate on a stone with the letter H and two numbers - 6 nd 3
The yellow marker plate on a a gate with the letter H and two numbers

Fire hydrants can be located in the following areas

  • Pavements
  • Roads
  • Verges
  • Private gardens
  • Public parks
  • Forestry