Common Path of Egress (CPOE)

Pls never mind the layout logic. This is for illustration only. 

I am confused with CBC-Common Path of Egress (CPOE) and wd like to ask:

1)   What is the discharge, the Green Dot or Pink Dot ?

2)   What is the CPOE, Blue only or Blue+Purple path?

3)   Consider the bldg is B-occupancy and sprinklered, which path is allowed to be 75' and which is allowed to be 250' max in length ?

4)   If the balcony is in between 3' and 5' to property line, it can be open-to-air (with guardrail) ? Yet the red window, at 5' line, has to be rated.

5)   Will the Cyan path (at elevator) be considered as dead end ?

6)   If the Elevator is equipped as an Egress Elevator, without being defined as an Elevator Lobby, should the Cyan path still be 8' minimum in one dimension?

7)   Does the wingwall in front has to be rated ?

8)   If this is the ground floor, and it has 80 occupants. The upper floor has 100 occupants, and the basement has 20 occupants. Should the pivot door be designed to capable of max of (80+100+20)/4 or (80+100+20)/2 ?

9)   And lastly, would the folding door at "BEASUM" room be considered as "horizontal exit" ? 

Thank you.





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Original Post

Since no one else has responded, I'll make an attempt at it.

I have no clue what this drawing is trying to depict. The scale is all over the place--either toilet compartments are undersized or swinging doors are huge. Annotations make no sense, so I don't know what use many of the spaces are.

If the blue line is intended to show the start of egress (black dot), it is in the wrong place--it should be at the most remote spot in the space. If that room (where egress begins) has one exit door to outside by elevator (I assume since there is no door swing symbol) and an exit access door to what appears to be some form of lobby, then there are two means of egress from that space, which means there is no common path of egress travel.

To answer your questions a best as possible:

Question 1: The exit discharge begins where an exit ends, thus the green line would represent the exit discharge.

Questions 2 & 3: For explanation of travel distance and common path of egress travel, read my article (

Question 4: I think you mean landing instead of balcony, but, as to your question, the answer is no. Fire separation distance is measured perpendicular to the building to a lot line, so the measurement would be from left to right, not from down to up.

Question 5: It's a dead end, but it maybe okay since there is no distance shown.

Question 6: If the elevator is used as an occupant evacuation elevator, then a lobby is required per Section 3008.

Question 7: Not enough information. If the lot line (I assume is the dashed line) run downward between the parking lot and the building, then most likely yes.

Question 8: Again, not enough information. My guess is that it would not.

Thank you Mr. Geren.

What a surprise I ran into you again. We exchanged emails a long while ago, >10 yrs, when I was a student (I am still), and I had downloaded all of yr pdf back then.

About my questions:

1)  This simple answer clears my head of the question "why didn't they call it as Egress Travel Distance instead of  Travel Distance ? ". Obviously because Discharge Distance is not part of it.

2)   For some FF&E reason as it has been shown, can the "blue path" be qualified as CPET (per exact wording of its definition) ? And if this is true, then this blue path can be as long as 75' if the "blue+cyan+a bit of orange" is 300' or less (in this B occupancy building) ?

8) & 9) I think you missed one question.

Thank you very much.

1) Travel within an exit (i.e., enclosed exit stairway or ramp, exit passageway, exterior exit stair) is also not included in the travel distance. Travel distance is measured from the most remote location in a space to the entrance of an exit. Once and exit is reached, travel distance is no longer measured. For example, you could technically travel thousands of feet within an exit passageway before reaching the exit discharge.

2) If FF&E create aisles that only provide a single path, then yes, that would be considered a common path of egress travel.

3) I skipped #8 apparently. My #8 response was meant for your #9 question. So, to answer your #8 question, the occupant load of the doors at the level of exit discharge shall be based on the greater of the occupant loads using the exit. The occupant loads of floors above or below are not compounded (See Section 1004.1.1.3, 2015 IBC). However, converging loads are per Section 1005.6 (2015 IBC). Thus, the occupant load of the ground floor is not added to the converging occupant loads of the basement and 2nd story. The basement story is permitted to have a single exit if the occupant load is less than 50 per IBC Table 1006.3.2(2); thus, all 20 occupants can egress up a single stairway. The 2nd story is required to have two exits, so the 100 occupants must be split between both exits; thus, one exit will have 50 and the other will have 50. The ground floor, with 80 occupants, is also required to have two exits with an even split, as well (40 and 40). Only 50% of the exits is permitted to egress through a lobby on the level of exit discharge (Section 1028.1, Exception 1). So if one of the stairs egresses through the lobby, the size of one of the exit doors on the ground floor will be based on the greater of the two occupant loads (40 occupants from the ground floor or 70 occupants from the converged occupant loads [50 + 20 = 70] of the basement and 2nd story), which will be the converging occupant loads. The second exit from the 2nd story must egress directly to the exterior, so those 50 occupants are not added to the occupant load on the ground floor.

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