Help...Calling all Engineers..!!

does anyone have a easy way to determine how much available water is in a hydrant after calculating your static pressure and your residual pressure?

is there any study info or study questions that anyone can remember for a written engineers exam?? any websites with sample hydraulic questions? any help would be great. Thxs

IFSTA Driver Operator.....

Check IFSTA Driver Operator/Pumper under the section that covers available water and hydrant operations (I don't recall the exact page # since my book is at work).

Hopefully, your Department uses the 10, 20, 30% (1st Degit Method) since it's easy enough to do in your head.

Here's how that method works:

Take the 1st digit (ex: 100 is 10) and multiply it by 1, 2, and 3. If the drop is between the number multiplied by 1 then you can add 3 like volume lines. If the number drop is above the number that comes from multipying by 1 and the number multiplyied by 2 then you can add 2 like volume lines; so on and so on.

If you're trying to determine your approximate static pressure while pumping then to do that how we do it is while pumping open another like-sized discharge that is capped or open the Tank-to-Pump Valve and note the drop. Once you note the drop add that to your current residual pressure and that will give you an approximate static pressure.

My only real issue with the Tank-to-Pump Valve is that if you open a 2 1/2" Valve like many Engines have then the flow will not be the same since there is less friction loss in the pipes of a 2 1/2" discharge.

I hope this helps.....