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907.2.1 sections Fire Alarm in occupancy? Whats included?

A

allis_ch

Member
Joined
Apr 16, 2010
Messages
25
What is the definition limit of the term "occupancy"?

907.2.1 - short version

Manual fire alarm is reqd in A occupancies with occupant load over 300.

How do you interpret this in regards to what area to include with the calculation?

If there is a church (A assembly occupancy) with a fire barrier separating the building into 2 fire areas, then do you use each fire area independently?

If each fire area is under 300 occupants, but the total is over 300, does it need a fire alarm system?

If there is a church (A assembly occupancy) with a fire wall separating the church into 2 buildings, then do you use each building independently?

If each building is under 300 occupants, but the total is over 300, does it need a fire alarm system?

In other areas of the building code, there are references to either fire areas, or building areas.

(Refer to the parallel wording in the sprinkler sections 903 where they removed the ambiguity of the language.)

I would assume that a true fire wall, makes it a different building, therefore you would probably restart the occupant calculations on each side of the fire wall.

How does it impact your decision when you consider the party wall and the old downtown buildings? You have no control over what happens on the other side of the party wall.
 
An occupancy could be seen as a tenant space even if not fire separated form adjoining spaces.

For an occupancy split by a fire separation wall it could still look like one occupancy especially if you egress from one through the other.
 
Depends...

You shot a lot of variables in your question

IMO

If just one building one business , the fire wall does not matter, only occupant load

"""""Only certain occupancies are required to have either a manual fire alarm or automatic fire detection system installed (see Figure 907.2). The need for either system is generally determined by the number of occupants, the height of the building or the ability of the occupants for self-preservation. Note that generally the fire alarm requirements are based upon occupancy not on fire area. Figure 907.2 contains the conditions that require either system must be installed in a building. The extent that an alarm system must be installed in a building once it has been etermined that such a system is required is based on a couple of factors. One if it is the only occupancy in the building then it would be required throughout the building. If the building is a mixed occupancy, it can wither be separated or nonseparated. If the occupancy is separated in accordance with Section 508.4, then the alarm system is only required whihin that portion of the building. If the building is considered a nonseparated mixed occupancy building, then Section 508.3.1 states that "the code apply to each portion of the building based upon the occupancy classification of that space and that the most restrictive applicable provisions of Section 403 and Chapter 9 shall apply to the building or portion thereof in which the nonseparated occupancies are located." Therefore, if you had a Group A occupancy in a nonseparated mixed occupancy (containing other occupancies such as Group B and M) where the Group A occupancy exceeds an occupant load of 300, then the entire nonseparated mixed occupancy would require the alarm system. Note that Section 508.3.1 focuses on each space to determine occupancy and requirements. Once the occupant load is determined, then any requirements such as fire alarms would be required throughout. The code does not address whether or not a nonseparated mixed occupancy has a completely independent means of egress such as in a strip mall. Additionally, take a building containing primarily Group A occupancies the code does not clearly address whether such occupancies within a building should be looked at as an aggregate or whether it is each individual space. Multiplex theaters, for example, could have many theaters all under 300, but since as an aggregate contain more than 300 and the fact that they are required to share at least 50 percent of their egress it may be viewed as a single occupancy and require an alarm system. Again, the code does not address this issue but the key to addressing these situations appears to be separation and egress. """"""
 
Once again your question has to many variables

If you want to refine it after you read the replies, please do
 
If a true fire rated separation exists to create separate “fire areas” then each is considered a separate A Use as applicable pending compliant egresss. The fire barrier or fire wall assembly would have to have or meet the requirements of the building code presently in Chapter 7 for A Uses (2 hours assembly). The term fire wall or party wall will take one back to a two hour assembly using the footnote.

So my opinion is that if the wall separating the Use is a compliant 2 hour fire rated assembly then the occupant load is figured separately for fire protection or alarm system regulations. The caveat is that if the separation has non-compliant openings the occupant loads of both sides are used to determine fire protection and alarm regulations.
 
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It was an opinion of your interpretation question.

I tend to believe that fire area is not relevant to this section.

So I figure that the occupancy is all that matters.

So I thought "OK so it doesn't even matter if there is a fire wall" and the buildings are separated ?

which seemed troubling to me.

Obviously separated buildings must have independent exits to the outside (less than 50% required exits could be horiz exits).

However I found myself wondering how others interpret this.

Part 2 of the question: (just to muddy the water)

After you think about that, then ask what happens to the old downtown building with a restaurant 1, beside a restaurant 2, beside a restaurant 3.

If the term building is not relevant, then what if these contiguous occupancies total over 300 occupants?

(If the calculation doesn't stop at the fire area, or at the building area, then does the calculation stop at the property line?)
 
From the Commentary.......

SECTION 907 FIRE ALARM AND DETECTION SYSTEMS
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FIRE AREA. The aggregate floor area enclosed and bounded by fire walls, fire barriers, exterior walls or horizontal assemblies of a building. Areas of the building not provided with surrounding walls shall be included in the fire area if such areas are included within the horizontal projection of the roof or floor next above. [F]
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This term is used to describe a specific and controlled area within a building that may consist of a portion of the floor area within a single story, one entire story or the combined floor area of several stories, depending on how these areas are enclosed and separated from other floor areas. Where a fire barrier with a fire-resistance rating in accordance with :Next('./icod_ibc_2009f2cc_7_par083.htm')'>Section 707.3.9 divides the floor area of a one-story building, the floor area on each side of the wall would constitute a separate fire area. If a horizontal assembly separating the two stories in a two-story building is fire-resistance rated in accordance with :Next('./icod_ibc_2009f2cc_7_par161.htm')'>Section 712.3, each story would be a separate fire area. In cases where mezzanines are present, the floor area of the mezzanine is included in the fire area calculations, even though the area of the mezzanine does not contribute to the building area calculations. See the commentary to :Next('./icod_ibc_2009f2cc_7_par083.htm')'>Sections 707.3.9 and :Next('./icod_ibc_2009f2cc_7_par161.htm')'>712.3 for further information. Note that fire walls are one way of creating fire areas but are typically used to create separate buildings.
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As motioned below (or above) the 2 hour fire barrier will create separate areas or buildings depending on exit arrangements and separate requirements for fire protection unless the openings are non-compliant. If they are continuous or non-separated, the occupant loads for all non-separated are applied to the fire protection and detection regulations.
 
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Sorry -

I don't know how to edit my post after it posted. Please read this in place of post #7 wording.

So I thought "OK so it doesn't even matter if there is a fire wall" OR IF the buildings are separated ?

which seemed troubling to me.

Obviously separated buildings must have independent exits to the outside (less than 50% required exits could be horiz exits).

However I found myself wondering how others interpret this.
 
FM William Bruns - Sorry - I don't see how what you quoted indicates anything about how Fire area stops the "occupancy" calculation.
 
I guess I am looking for a code definition on the limit of "occupancy".

I can see the code definition for fire area, and

I can see the code definition for building area.

I would have to assume from the lack of anything else that the assembly occupancy continues all across the entire church.
 
It is clearly spelled out in the code

[F] 907.2.1 Group A.

A manual fire alarm system that activates the occupant notification system in accordance with Section 907.5 shall be installed in Group A occupancies where the occupant load due to the assembly occupancy is 300 or more. Group A occupancies not separated from one another in accordance with Section 707.3.9 shall be considered as a single occupancy for the purposes of applying this section.

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 waterflow.

In the real world of codes the "manual fire alarm" requirement is a mute section for assemblies as any assembly occupancy of 300 or more will have a sprinkler which will require automatic notification.
 
Part 2 of the question: (just to muddy the water)After you think about that, then ask what happens to the old downtown building with a restaurant 1, beside a restaurant 2, beside a restaurant 3.

If the term building is not relevant, then what if these contiguous occupancies total over 300 occupants?

(If the calculation doesn't stop at the fire area, or at the building area, then does the calculation stop at the property line?)
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The only mud in the waters is the misapplication of a code section

[F] 907.2 Where required—new buildings and structures.

An approved fire alarm system installed in accordance with the provisions of this code and NFPA 72 shall be provided in new buildings and structures in accordance with Sections 907.2.1 through 907.2.23 and provide occupant notification in accordance with Section 907.5, unless other requirements are provided by another section of this code.

907.2 does not apply to existing buildings

You need to start in the IEBC and you will probably find the requirements would be limited to the work area only
 
allis_ch said:
"building" meaning portions separated by fire walls
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allis_ch said:
It was an opinion of your interpretation question.I tend to believe that fire area is not relevant to this section.

So I figure that the occupancy is all that matters.

So I thought "OK so it doesn't even matter if there is a fire wall" and the buildings are separated ?

which seemed troubling to me.

Obviously separated buildings must have independent exits to the outside (less than 50% required exits could be horiz exits).

However I found myself wondering how others interpret this.

Part 2 of the question: (just to muddy the water)

After you think about that, then ask what happens to the old downtown building with a restaurant 1, beside a restaurant 2, beside a restaurant 3.

If the term building is not relevant, then what if these contiguous occupancies total over 300 occupants?

(If the calculation doesn't stop at the fire area, or at the building area, then does the calculation stop at the property line?)
Click to expand...
You did not muddy them, you made them completely dark

"""

Part 2 of the question: (just to muddy the water)

After you think about that, then ask what happens to the old downtown building with a restaurant 1, beside a restaurant 2, beside a restaurant 3.

If the term building is not relevant, then what if these contiguous occupancies total over 300 occupants?

(If the calculation doesn't stop at the fire area, or at the building area, then does the calculation stop at the property line?)"""

Each business would be treated independently ,,,, like a strip center
 
allis_ch said:
I guess I am looking for a code definition on the limit of "occupancy".I can see the code definition for fire area, and

I can see the code definition for building area.

I would have to assume from the lack of anything else that the assembly occupancy continues all across the entire church.
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Check page 27 does not answer all your questions

http://www.ocfa.org/_uploads/pdf/guidee04.pdf
 
mtlogcabin- thank you for your reply-

That certainly cleared it up- however..

Which version of the code do you have?

My 2006 doesn't have that second sentence in it.

That changes things if that added that.

Now I can see the fire barrier comments for fire area would come into play.
 
It is the same language

F]907.2 Where required.

An approved manual, automatic or manual and automatic fire alarm system installed in accordance with the provisions of this code and NFPA 72 shall be provided in new buildings and structures in accordance with Sections 907.2.1 through 907.2.23 and provide occupant notification in accordance with Section 907.9, unless other requirements are provided by another section of this code. Where automatic sprinkler protection installed in accordance with Section 903.3.1.1 or 903.3.1.2 is provided and connected to the building fire alarm system, automatic heat detection required by this section shall not be required.

What second sentence are you referring to?
 
The 2006 version doesn't say

"Group A occupancies not separated from one another in accordance with Section 707.3.9 shall be considered as a single occupancy for the purposes of applying this section."
 
How about a multi plex theater with five theaters, two hour wall between them with occupant load of 200 in each theater and all theaters dump into common entry exit foyer/ corridor .

Does it need a fire alarm system
 
allis_ch said:
The 2006 version doesn't say "Group A occupancies not separated from one another in accordance with Section 707.3.9 shall be considered as a single occupancy for the purposes of applying this section."
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Your correct it is not in the 2006

You comments/questions need to clarify if you are referring to existing buildings or new construction. Sprinklers and alarm requirements under Chapter 9 are applicable to NEW construction only. You have to find the charging language in the IEBC before you can use portions of Chapter 9 in existing buildings.

Manual fire alarm requirements in new buildings are not determined by the size of the fire area. They are determined by the number of occupants within a Group occupancy.

Manual fire alarm requirements in existing buildings are determined by a number of variables under the IEBC

The IFC required retroactive fire alarms in existing buildings based on the occupancy. See Section 907.3 Of the 2006 IFC. Assemblies are not included
 
cda said:
How about a multi plex theater with five theaters, two hour wall between them with occupant load of 200 in each theater and all theaters dump into common entry exit foyer/ corridor .Does it need a fire alarm system
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Yes

2006 IBC

[F]907.2.1 Group A.

A manual fire alarm system shall be installed in Group A occupancies having an occupant load of 300 or more. Portions of Group E occupancies occupied for assembly purposes shall be provided with a fire alarm system as required for the Group E occupancy.

No exceptions for fire areas or fire barriers or any other exceptions. A manual fire alarm system will be required

Now your scenario might eliminate the sprinkler requirements but it does not negate the manual fire alarm requirements
 
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