We have a long, narrow basement space which will be used for storage. Because of the direction of the structure, we plan to cover the long but narrow space by two branch lines with 8 sprinklers on each line. When we're trying to determine the remote area, NFPA 13 says that the minimum length along the branch line must be 1.2 x √(remote area), which for us is 2,000 sqft. This comes out to a minimum of six sprinklers. However, if we have two branch lines with six sprinklers each, we only reach 1,560 sqft.
Is there a maximum number of sprinklers that is required to be calculated along a branch line, or for narrow spaces does the design area just take a very long and narrow coverage until it reaches the required size, regardless of how it lays against the branch lines?
Thanks in advance!
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