In a recent Q&A on the FacilityCare website, consultant Brad Keyes answered a question about sprinklers in air handlers. 

Q: Does a rooftop air handler require sprinkler heads if it is unoccupied? We have large walk-in-style air handlers on the roof of our hospital, and they are not protected with automatic sprinklers.

A: Section 18.3.5.1 of the 2000 Life Safety Code (LSC) requires buildings containing healthcare facilities to be protected throughout with automatic sprinklers. Initially, one could make the case that mechanical equipment sitting outside the building (although on top of the building) is not part of the building and therefore is not included in this requirement. Taking a look at NFPA 13 (1999 edition), I see section 5-13.6 requires sprinklers in elevator equipment rooms and section 5-13.11 requires sprinklers in electrical rooms (with some exceptions). But these rooms are actually inside the building and would be required to be protected with sprinklers according to section 18.3.5.1 of the 2000 LSC.

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