Fire alarm requirments for a commercial building group 'B'

Cartoon1

Cartoon1

Senior Member
Location
Florida
Occupation
Electrical Engineer
Per florida building code:
A manual fire alarm system, which activates the occupant notification system in accordance with Section 907.5, shall be installed in Group B occupancies where one of the following conditions exists:

  1. 1.The combined Group B occupant load of all floors is 500 or more.
  2. 2.The Group B occupant load is more than 100 persons above or below the lowest level of exit discharge.
  3. 3.The fire area contains an ambulatory care facility.
Exception: Manual fire alarm boxes are not required where the building is equipped throughout with an automatic sprinkler system installed in accordance with Section 903.3.1.1 and the occupant notification appliances will activate throughout the notification zones upon sprinkler water flow.

My building is a single story building. With an occupant load of 200 (Florida). Group B building. Not Sprinkled. Based on the above it dosent need a fire alarm system from my understanding. Does number (2) of The Group B occupant load is more than 100 persons above or below the lowest level of exit discharge play a role in a single floor building? I find #2 a bit confusing.

Thank you,
 
Cartoon1 said:
My building is a single story building. With an occupant load of 200 (Florida). Group B building. Not Sprinkled. Based on the above it dosent need a fire alarm system from my understanding. Does number (2) of The Group B occupant load is more than 100 persons above or below the lowest level of exit discharge play a role in a single floor building? I find #2 a bit confusing.
Click to expand...
Item #2 simply means the lowest floor in the building from which people will exit in an emergency. Assuming the ground floor is the level from which people will exit the building, as long as you do not have a basement below the ground floor, which can hold more than 100 people, per FBC occupancy calcs, the building would not require fire alarm system.

If you do have a basement below the ground floor which can hold 100 people or more, a fire alarm system meeting the FFAC requirements will be required.

Alternatively, let's say the same building did have a basement that can hold 100 or more people but the building is built into a hillside which allows exit discharge out of the basement. Now the basement is the lowest level of exit discharge so a fire alarm system would not be required. Keep in mind that the exit discharge floor must also meet all the requirements of distance travel to exit to be considered the level of exit discharge. The basement cannot be 100,000 square feet with one door exiting to grade in the corner of the basement. That will certainly not meet max allowable distance travel to exit everyone in the basement out of that door. Many will need to travel to the ground floor to exit the building. Best to confirm all of this with the architect or the life safety plans prepared for the building if they are available. If not you will need to determine all of this using the FBC.

I have always opted to add the system into the design if I was unsure. I've never had someone question why I included a fire alarm system in a design. When it is not included is when the questions come into play.
 
Sparky2791 said:
...
Alternatively, let's say the same building did have a basement that can hold 100 or more people but the building is built into a hillside which allows exit discharge out of the basement....
Click to expand...
Consider now, a building with the 1st floor level with the top of the hill, allowing discharge with the proper travel, and the basement you described. Both levels meet the requirements of the definition, so even if you had 200 people on each level, no fire alarm system required.

In practice, the sharper-eyed among us will wonder how the sprinkler system is going to activate the "occupant notification system." Why, they'll hook it up to the fire alarm system that you otherwise don't need and wire the notification appliances from that.
 
gadfly56 said:
the sharper-eyed among us will wonder how the sprinkler system is going to activate the "occupant notification system."
Click to expand...
OP indicated the building is 'not' sprinklered......but......I do see your point and have often asked how a building that requires a sprinkler system does not require a fire alarm system. My only 'argument' is the IFC say shall activate the occupant notification system where required as another part of this code. (I did not look to see exactly what is says so that is somewhat of a guess at the quoted text)
 
gadfly56 said:
Consider now, a building with the 1st floor level with the top of the hill, allowing discharge with the proper travel, and the basement you described. Both levels meet the requirements of the definition, so even if you had 200 people on each level, no fire alarm system required.
Click to expand...
Not sure I follow you on this....... 1st floor level with the top of the hill? Also there can only be one lowest level.
 
You must log in or register to reply here.
Top