The first issue involves fire alarm smoke detection and electro-magnetic door holders. The NFPA 72: National Fire Alarm and Signaling Code (2010)
"2-10.6.5.1.1 If the depth of wall section above the door is 24 inches (610 mm) or less, one ceiling mounted detector shall be required on one side of the doorway only."
"2-10.6.5.1.2* If the depth of wall section above the door is greater than 24 inches (610 mm), two ceiling mounted detectors shall be required, one on each side of the doorway."
Location
"2-10.6.6.1 If ceiling mounted smoke detectors are to be installed on a smooth ceiling for a single or double doorway, they shall be located as follows (Figure 2-10.6.5.3.1 shall apply):
- On the center line of the doorway.
- No more than 5 feet (1.5 m) measured along the ceiling and perpendicular to the door way. (Figure 2-10.6.5.1.1 shall apply.)
- No closer than shown in Figure 2-10.6.5.1.1, parts B, D and F.
It is amazing to me to see some of the bad installations out there and to think of the law suits that could come due to negligence like this. Read about the other code violation I found here.

NFPA 72 gives rules for placement of the smoke detectors where they are required by code to trigger the door to close. Not all doors with holders require smoke detectors to trigger them. Regardless the fire alarm must de-energize the magnetic hold opens, but maybe the door in that pic didn't need smokes to close it.
ReplyDeleteThese doors do require system smokes to close as it is located on a fire wall. That is the reason for the smoke placement by NFPA 72 if the header is greater than 24". As far as the FACP releasing power to the mags, you are correct.
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