Make sure you stand on the opposite side of that 5 inch cap, just in case it's loose while your opening the hydrant cause that pressure will shoot that cap out and that'll be the end of your knee.
It would only have to be per NFPA 13 if the flow test data was being used to design a sprinkler system. I should actually retract the statement above after watching the video a 2nd time. We use a pito tube to measure discharge pressure, which I didn't see and lead me to question the test. On second view, a pito tube is not necessary since the apparatus has a built in gauge. I would like to know where to get one, those are nice. Must have a calculated chart for pito pressure to GPM.
why does it have to be per nfpa 13? I run a lot of fire flows that have nothing to do with sprinkler installs and design. if my test indicates adequate flow and dependent on the building type/size/design/use/materials/etc, i'll have my engineer issue an ability to provide fire flow and no sprinklers will be required.
Could be using a different Discharge Coefficient for the hydrant. If using a Coefficient of 0.85, average between the smooth transition and a sharp transition, the results for 55 psi would be approx. 1,175 gpm. Not sure how that gauge is reading though...guys are saying the gauge converts into flow on the readout....hmm....