Sprinkler Design

[jhoover]

I am reviewing a sprinkler design submitted for our locality. Their required pressure is under our static pressure, but it exceeds our residual. Are sprinkler designs supposed to have the required pressure of each zone meet static only or residual too? It seems the designer thinks as long as the static is met. I've looked in NFPA 13 and don't see the answer to this question.

 

[bimr]

Check the listing of the individual sprinkler to see what the operating pressure of that specific sprinkler is. Also check how much water is flowing out of the most demanding head. This is determined by hazard classification of the area the head is protecting and how many square feet the head is covering. NFPA 13 sets a minimum pressure of 7 psi (0.48 bar) at the end sprinkler in any event, so that a proper spray umbrella is ensured.

The standard requires that the water supply for a home fire sprinkler system accommodate one or two operating sprinklers for a period of seven to 10 minutes.

Their required pressure is under our static pressure, but it exceeds our residual. Are sprinkler designs supposed to have the required pressure of each zone meet static only or residual too? It seems the designer thinks as long as the static is met.

Not sure what you mean by this. Static pressure should normally be higher than residual pressure. The sprinklers should work with residual pressure.

Do you have calculations and the sprinkler data sheet?

Water Supply

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