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We calculate the supply worts capacity for each representative needed fire flow test location. In doing this, ISO considers a variety of water supply sources. These would include public water supplies, emergency supplies (usually accessed from neighboring water systems), suction supplies (usually evidenced by dry hydrant installations near a river, lake or other body of water), and a supply developed by a fire department using large diameter hose or vehicles to shuttle water from a source of supply to a fire site. The result is expressed in gallons per minute(gpm). The normal ability of the distribution system to deliver Needed Fire Flows (NFF) at the selected building locations is reviewed. The results of a flow test at a representative test location will indicate the ability of the water mains (or fire department in the case of fire department supplies)to carry water to that location. The hydrant distribution is reviewed within 1,000 feet of representative test locations measured as hose can be laid by apparatus. Credit is allowed up to 1,000 gpm from each hydrant within 300 feet of the location, 670 gpm from hydrants within 301 to 600 feet of the location and 250 gpm from hydrants within 601 to 1,000 feet of the location. The normal distribution of hydrants in the vicinity of test locations considered in Items 612 and 613 are evaluated. These hydrant distribution allowances are based upon a standard fire hydrant with a pumper outlet conforming to the American Water Works Association (AWWA) Standard C-502 or C-503. In addition, they are based upon a standard complement of 1,200 feet of 2% inch fire hose. If a hose diameter greater than 2% inch is carried by all in-service pumpers, the hydrant distribution credit may be greater than that stated above due to the reduced friction loss in the larger diameter hose. Where there are 2 or more systems or services distributing water at the same location, credit is given on the basis of the joint protection provided by all systems and services available. A. Sub-standard type hydrants with at least one fire department outlet are considered if they are capable of delivering at least 250 gpm. B. A cistern or other suction point must be capable of supplying 250 gpm for at least 2 hours to be recognized. C. The maximum credit for a hydrant may be limited by A or B above and is limited by the number and size of outlets as follows: MAXIMUM CREDIT At least one pumper outlet 1,000 gpm Two or more hose outlets, no pumper outlet 750 gpm One hose outlet only 500 gpm For maximum credit in the FSRS, the needed fire flows should be available at each location in the district. Needed fire flows of 2,500 gpm or less should be available for 2 hours; and needed fire flows of 3,000 and 3,500 gpm should be obtainable for 3 hours. A variety of buildings were used as representative building locations in the city to determine the theoretical amount of water necessary for fire suppression purposes(needed fire flow). The points calculated for Vero Beach resulted in the following: CSS = 29.14 ©ISO Properties,Inc.,2007 Page 30