Multiple Means of Egress - One Exit Blocked

[Mech]

2009 IBC

Existing Building with a proposed addition.

There are 3 exit doors, one of which is located in an existing conference room. This conference room (total occupant load = 221 people) utilizes a code reader to limit access from the office area. The conference room exit door capacity is 160 people. The remaining 61 people need to egress back through the office area. (The doors are not locked to occupants inside the room.)

1005.1 Minimum required egress width.

The means of egress width shall not be less than required by this section. The total width of means of egress in inches (mm) shall not be less than the total occupant load served by the means of egress multiplied by 0.3 inch (7.62 mm) per occupant for stairways and by 0.2 inch (5.08 mm) per occupant for other egress components. The width shall not be less than specified elsewhere in this code. Multiple means of egress shall be sized such that the loss of any one means of egress shall not reduce the available capacity to less than 50 percent of the required capacity. The maximum capacity required from any story of a building shall be maintained to the termination of the means of egress.

Exception: Means of egress complying with Section 1028.

When sizing multiple means of egress to ensure 50% capacity in case one of the three exit doors is blocked, can I utilize this conference room door as being available? I am thinking I can because the door is at full capacity using occupants in this room alone.

What say you?

 

[cda]

Well not sure of your thought process , hope the 61 people know to use the other exit

Your exiting is possible if you meet the intervening room rule

And the doors have panic hardware on the egress side

A little hard to give a solid answer with out a floor plan

 

[Mech]

Here's a sketch.



Assume either Exit 1 or 2 is blocked.

 

[cda]

Sorry forgot panic hardware is a,h,e

Cannot find door swing thought it was 100

Have you taken into account travel distance, cpet

And how the new addition will figure into all this

 

[cda]

1014.2 Egress through intervening spaces. Egress through intervening spaces shall comply with this section.

1. Egress from a room or space shall not pass through adjoining or intervening rooms or areas, except where such adjoining rooms or areas and the area served are accessory to one or the other, are not a Group H occupancy and provide a discernible path of egress travel to an exit.

Exception: Means of egress are not prohibited through adjoining or intervening rooms or spaces in a Group H, S or F occupancy when the adjoining or intervening rooms or spaces are the same or a lesser hazard occupancy group.

2. An exit access shall not pass through a room that can be locked to prevent egress.

3. Means of egress from dwelling units or sleeping areas shall not lead through other sleeping areas, toilet rooms or bathrooms.

4. Egress shall not pass through kitchens, storage rooms, closets or spaces used for similar purposes.

Exceptions:

1. Means of egress are not prohibited through a kitchen area serving adjoining rooms constituting part of the same dwelling unit or sleeping unit.

2. Means of egress are not prohibited through stockrooms in Group M occupancies when all of the following are met:

2.1. The stock is of the same hazard classification as that found in the main retail area;

2.2. Not more than 50 percent of the exit access is through the stockroom;

2.3. The stockroom is not subject to locking from the egress side; and

2.4. There is a demarcated, minimum 44-inch-wide (1118 mm) aisle defined by full- or partial-height fixed walls or similar construction that will maintain the required width and lead directly from the retail area to the exit without obstructions.

 

[cda]

Sorry it is 50

Doors shall swing in the direction of egress travel where serving an occupant load of 50 or more persons or a Group H occupancy.

 

[RLGA]

If a door is a standard 3'-0" door, you'll have a clear width of about 33.5". This means that each door has a capacity of 167 occupants. Therefore, two doors will provide the required capacity for an occupant load of 221.

However, any door that can be used for egress, even those in excess of what is required, must comply with all requirements for egress doors. Thus, all doors must swing in the direction of egress travel, since the occupant load served (221) exceeds 50. This also means any egress door downstream along egress path; thus, the swing direction of some of the corridor doors will need to be reversed.

It appears the loss of any one door will not reduce the capacity to less than 50%.

Passage through the office area, in my opinion, would be acceptable. I have seen many conference rooms located in the center of open office areas, which means all egress doors from the conference room pass through the office area.

 

[Mech]

CPET is good when no exits are blocked. I never read that CPET has to be figured with an exit blocked.

Door swing is set to open in direction of travel. If it opens against direction of travel, only 49 occupants were assumed to pass through the door.

The only question I had was the existing conference room and the electronically locked doors.

 

[cda]

CPET is good when no exits are blocked. I never read that CPET has to be figured with an exit blocked.Door swing is set to open in direction of travel. If it opens against direction of travel, only 49 occupants were assumed to pass through the door.

The only question I had was the existing conference room and the electronically locked doors.

If the conference room is allowed as a means of egress

To me at least one door going into the conference room would have to swing into the room.

That door would have to meet requirements for locking hardware for a code complying exit door

No cpet is not based on a blocked exit

Building Code: Common Path of Travel | M Group Blog

NFPA :: News & Publications :: NFPA Journal® :: Archived Issues :: November/December 2008 :: Columns

 

[JPohling]

I do not know how your getting an occupant load of 221 in that conference room as shown? Other than that it looks doable.

 

[cda]

I do not know how your getting an occupant load of 221 in that conference room as shown? Other than that it looks doable.

It would be around 3300 sq ft

May be the 221 comes from the occupant load of the entire office area

 

[RLGA]

Door swing is set to open in direction of travel. If it opens against direction of travel, only 49 occupants were assumed to pass through the door.

That is incorrect. It is not based on the number of occupants determined to egress the door, it is based on the number of occupants in total that is served by that door. Here's the excerpt from the Commentary:

A side-hinged door must swing in the direction of

egress travel where the required occupant capacity of

the room is 50 or more. As such, a room with two

doors and an occupant load of 99 would require both

doors to swing in the direction of egress travel, even

though each door has a calculated occupant usage of

less than 50.

 

[Mech]

I do not know how your getting an occupant load of 221 in that conference room as shown? Other than that it looks doable.

1038 sf @ 5 sf/person standing room = 208 people and there are other areas inside the electronically locked double doors to increase the load to 221.

That is incorrect. It is not based on the number of occupants determined to egress the door, it is based on the number of occupants in total that is served by that door. Here's the excerpt from the Commentary: A side-hinged door must swing in the direction of

egress travel where the required occupant capacity of

the room is 50 or more. As such, a room with two

doors and an occupant load of 99 would require both

doors to swing in the direction of egress travel, even

though each door has a calculated occupant usage of

less than 50.

RLGA - Is this saying a room requiring two exits with an occupant load of 51 would require both doors to open in the direction of travel?

 

[cda]

1038 sf @ 5 sf/person standing room = 208 people and there are other areas inside the electronically locked double doors to increase the load to 221.RLGA - Is this saying a room requiring two exits with an occupant load of 51 would require both doors to open in the direction of travel?

Yeppers

If there are some tables and chairs in the conference room, you could go to 15, but would not matter still over 50

 

[RLGA]

RLGA - Is this saying a room requiring two exits with an occupant load of 51 would require both doors to open in the direction of travel?

Yes, both doors would need to swing in the direction of egress travel.

 

[AegisFPE]

The 2012 makes it clearer that both doors need to swing in the direction of egress travel.

 

[cda]

Yes, both doors would need to swing in the direction of egress travel.

But if the building goes down to only two exits, the rest of the office might use the doors going into the conference room, to get to door 3. So it seems you need one door swing one way and the other swing opposite

 

[RLGA]

What is more likely, a large group egressing out of the conference room or some occupants having to exit through the conference room?

Besides, the office area adjacent to the conference room probably has an occupant load that is less than 50 and would not require any doors to swing in the direction of egress travel.

 

[cda]

But if you take the entire building down to only two exits

There is a possibility of a lot of people going towards door 3

Plus the code does not in a way take which exit a person might use.

Plus if door swing is not correct, there might be a dead end corridor issue

I think the exiting trying to be done is not good

 

[LGreene]

I'm not sure if I'm understanding this correctly...are you asking if people can travel through the existing conference room to get to Exit 3? Exit 3 can serve the existing conference room, but in addition to the door swing issue on the door leading to that conference room, the door is locked on the office side, correct?

 

[cda]

that is what I have been trying to say, finally I get one more vote!!!!!!

 

[RLGA]

What is the occupant load of the entire area? Are three exits required, or, in other words, does the total occupant load exceed 500?

If not, then Exit 3 need only serve the conference room. If the door into the corridor for the office area in the lower left of the building is reversed in swing direction and not locked, then a dead end condition would not exist.

 

[cda]

Sorry all I got wayyyyy off base.

Went back and read op and finally clicked

New position is

1 look to see if the entire office can exit per code using door 1 and 2. Only

2 if the answer to # 1 is yes, then do not try to exit anyone from the office through the conference room

3 except the people in the conference room and the two rooms on

The conference room side of the doors

4 the conference room still is required two exits, and the door hardware has to meet code, so no card reader to egress the conference room to the office area

 

[cda]

Finally agree with rlga in this set up because of the occupant load, if you only have two exits and lose one, you are still good to go, since not over the 50% rule