Dry Fire Hydrant Design 04 - The Importance of Testing
By President Mark Davis
September 27, 2013
The inspection and flowtesting of dry fire hydrants is important. To get maximum credit in the ISO rating schedule - dry fire hydrants should be inspected quarterly and flowtested annually - and of course - all that work needs to be recorded and filed. Alot can happen to a dry hydrant in the course of a year.
In the dry fire hydrant highlighted in this News Story - the silicone sealant was sucked out during the flowtest. Obviously - this should not have happened - but it did. Interestingly enough, the pumper that was drafting is equipped with an automatic air primer and never once had an air leak issue while drafting -even though the sealant was gone in the DFH head.
Annual flowtesting is a must for any dry fire hydrant service program. Recording-keeping should show changes in flows as well as record maintenance activities.
A bit of problem!
The 1,500 gpm pumper pulled the silicone sealant out of the inside of the suction head. Fortunately, the automatic air primer on the pumper handled any air leakage and a 1,000 gpm flow was obtained.
