Fire Alarm Strobe in Corridor with 30’ Ceiling

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Zent1121

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If I am placing strobes in a corridor that has a ceiling height of 30’ can the strobes be set to 15Cd? I know Nfpa states that they cannot be less than 15Cd in corridors but that seems low for a 30’ mounting height. I couldn’t find any other information on this. Any help is appreciated
 
Is it mounted to the ceiling or wall? If wall:
18.5.5 Appliance Location.
18.5.5.1 Wall-mounted appliances shall be mounted such that the entire lens is not less than 80 in. (2.03 m) and not greater than 96 in. (2.44 m) above the finished floor or at the mounting height specified using the performance-based alternative of 18.5.5.7.
 
ron said:
Is it mounted to the ceiling or wall? If wall:
18.5.5 Appliance Location.
18.5.5.1 Wall-mounted appliances shall be mounted such that the entire lens is not less than 80 in. (2.03 m) and not greater than 96 in. (2.44 m) above the finished floor or at the mounting height specified using the performance-based alternative of 18.5.5.7.
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They’re ceiling mounted. Being brought down from the deck to 30’ AFF.
 
Zent1121 said:
They’re ceiling mounted. Being brought down from the deck to 30’ AFF.
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There are separate rules for ceiling mount. The 15-candela deal is ONLY for wall mounted. And the corridor has to be no more than 20 feet wide.

Ceiling Mount Strobes.PNG
Looking at the table, you'd need to set the strobes for 55 candela for a 20-foot wide corridor.
 
gadfly56 said:
There are separate rules for ceiling mount. The 15-candela deal is ONLY for wall mounted. And the corridor has to be no more than 20 feet wide.

View attachment 2567249
Looking at the table, you'd need to set the strobes for 55 candela for a 20-foot wide corridor.
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Thank you for the response I really appreciate the help but the table you showed is part of what is throwing me off. The table says it is for room spacing for ceiling mounted devices not corridor. If the table also applies to corridor that makes sense but I haven’t seen anything stating that it does. I also didn’t know there are separate rules for corridor and ceiling, as 18.5.5.5.3 says “In a corridor application, visible appliances shall be rated not less than 15 cd.” I assumed that applied to both wall and ceiling mount devices but with the ceiling device being mounted at 30’ AFF that didn’t seem right and is why I am asking. Again thanks for the help I do appreciate it.
 
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IMO, a corridor is technically a room, so the chart would apply unless something overrides it. As in, a corridor is a room, but a room is not necessarily a corridor.
 
Strathead said:
IMO, a corridor is technically a room, so the chart would apply unless something overrides it. As in, a corridor is a room, but a room is not necessarily a corridor.
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Corridors less than 20 feet wide require an appliance within 15 feet of each end, and at separations of 100 feet, so a corridor 130 feet long needs 3 devices. I've never seen a corridor with 30' ceilings. The code is a little vague regarding the mounting going up to 30 feet, but it does allow for ceiling mounting in corridors. So, assuming the ceiling mounting is OK, with room spacing you'd need a device every 40 feet.
 
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