by Jerry Peck - Codeman on Wed Jan 26, 2011 11:30 pm
Hi Chris,
That is found in the installation instructions for the smoke detectors. The smoke detectors need to be at least 3 feet from an air disturbing source, which would include returns, supplies, and the ends of the blades of ceiling fans. Note that "air disturbing source" is the term I use to describe sources which disturb the air and which the smoke detectors need to be away from, I have forgotten the precise wording in the installation instructions as the various installation instructions used slightly different wording - I just found that "air disturbing source" was descriptive and readily understood as to why it should not be close to the item disturbing the air, you want the smoke to get to the detector, not be sucked or blown away from the detector.
I have seen some smoke detectors in years past which said 5 feet from the air disturbing source, but recently it seems that 3 feet is the new standard clearance.
Jerry Peck - CodeMan
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