What is the NFPA Standard for hydrants?

NFPA 291 provides guidance on fire flow tests and marking of hydrants in order to determine and indicate the relative available fire service water supply from hydrants and to identify possible deficiencies which could be corrected to ensure adequate fire flows as needed.

What are the two types of modern fire hydrants?

Both wet- and dry-barrel hydrants typically have multiple outlets. Wet barrel hydrant outlets are typically individually controlled, while a single stem operates all the outlets of a dry barrel hydrant simultaneously.

How do you measure a fire hydrant?

Take a static pressure reading. Measure the inside diameter of the outlet nozzle or hydrant outlet where flow occurs. A hydrant’s inside diameter is usually 4”. Field personnel should slowly open each fire hydrant, one at a time, to avoid pressure surges.

How many meters is allowed from the location of a fire hydrant?

Stay away at least 4 meters from a fire hydrant, entrance to and fire station.

What is the standard radius distance of hydrant points?

Hydrants should be located at a distance of not less than 2 m from the face of the buildings. This distance may suitably be increased up to maximum 15 m where hydrants are installed to protect hazardous storages or processes so that the haydrants remain approachable and workable even in the case of a serious fire.

How much pressure is in a fire hydrant?

1.8. 4 The pressure in the hydrant pipe work shall be kept constant at 6 Kg/cm2. In the event of fire when any of the hydrant valve in the network is opened, the resultant fall in header pressure shall start the AC motor driven fire pump through pressure switches automatically.

What is hydrant system and types?

Dry barrel and wet barrel are the two kinds of Fire Hydrants. The wet barrel fire hydrant holds a constant water supply, while the dry barrel fire hydrant needs to have a valve release to let water in. It is designed to provide rapid access to water in the event that a fire breaks out.

How do you do a 2 hydrant flow test?

A pressure gauge is placed on one hydrant to record the static pressure; this is hydrant #1. The remaining two hydrants are opened to allow water to flow out as fast as possible. A hand-held pitot pressure gauge is used to measure the residual pressure while water is flowing from hydrants #2 and #3.