Fire Hydrants

Fire Hydrant with Missing CapI ran across this fire hydrant while I was in southern California. It appears to me that the organization has failed to conduct basic routine inspections since the cap is missing from one of the hose connections. One of the reason why the caps are there in the first place is to prevent individuals from stuffing trash into the hydrant, thereby making it inoperable when they are needed.

NFPA 25 (1998 edition) is the standard which fire hydrants need to be maintained, tested and inspected. NFPA 25 defines hydrants in three configurations:

– Wall hydrants

– Dry barrel hydrants

– Wet barrel hydrants

For the purpose of this posting, we will only discuss the dry barrel and wet barrel hydrants.

Dry barrel hydrants are the most common type used, and are specified in environments where freezing temperatures could cause ice to form in the barrel. There is a control valve at the bottom of the barrel, well below the frost line. When water is needed, a fire fighter will connect a hose to one of the threaded connections and then will turn the valve stem at the top of the hydrant which will release water to the barrel and eventually to the hose outlet. When the control valve is closed, there is a relief valve at the bottom of the barrel (below frost line) to relieve the water from the barrel, so it can drain.

Wet barrel hydrants (like the one in the picture) are used in environments where freezing conditions are not a concern. Each outlet on the wet barrel hydrant has a control valve. Water pressure is maintained in the barrel and when an outlet valve is opened, water will flow.

Annual Inspection 

Not all fire hydrants located on a hospital campus may belong to the city. A discussion with the municipal water department will reveal which hydrants are the city’s and which hydrants belong to the healthcare organization. After you determine which hydrant you are responsible for, the following inspection program must be conducted annually, and after each operation. For dry barrel hydrants:

  • Accessibility:   Make sure the hydrant is accessible for fire fighters
  • Leaks:  Inspect for leaks. May represent a faulty control valve; damage due to freezing; or a faulty drain
  • Cracks:   Inspect for cracks which may be caused by freezing
  • Tightness of outlets:   Lubricate as needed
  • Worn nozzle threads:    Repair or replace
  • Worn control valve operating nut:   Repair or replace
  • Availability of operating wrench:   Make sure a wrench is available.

For wet barrel hydrants:

  • Accessibility:   Make sure the hydrant is accessible for fire fighters
  • Leaks:  Inspect for leaks. May represent a faulty control valve
  • Tightness of outlets:   Lubricate as needed
  • Worn nozzle threads:    Repair or replace
  • Worn control valve operating nut:   Repair or replace
  • Availability of operating wrench:   Make sure a wrench is available.

images[2]Hydrants have to be flow-tested annually to ensure proper operation. Each hydrant must be opened fully (slowly) and allow water to flow until all foreign material has been flushed, or until one minute has passed, whichever is longer. Then the hydrant control valve is closed and for dry barrel hydrants, ensure water drains from the barrel. Allow up to 60 minutes for the water to drain. This flow test is commonly accomplished with a Hose Monster (see picture at left) for safety.

Hydrant caps need to be lubricated annually to ensure they are in good operating condition if they are ever needed. During the winter months, keep snow and ice from accumulating around the hydrant to allow clear access for fire fighters.

 

 

 

 

no_parkingAnd don’t park your cars next to a hydrant, or it will end up looking like this: