Anything less than 2.5 gpm (gallons per minute) counts. There should be a label on the showerhead. If you can't find one, you can always rely on the saucepan method. Take a saucepan of known volume (4 quarts to a gallon), and run it under the shower (on cold!) to see how many times it fills up in a minute.
Completed on May 27, 2009 at 2:03 a.m.