Commercial Inspection - Doors 2

[John Bowman]

Question:
Doors located in 2HR rated occupancy separation walls shall have the following rating...

Choices:
20 mins
30 mins
60 mins
120 mins
90 mins

[Bruce M. Graham]

. .

[Marcel R. Cyr]

John, that is a good one. It is obvious to me that you have picked a good poll.

Thanks

Marcel

[Barry Adair]

The answer is contained within this doc

http://www.steeldoor.org/res/118.pdf

[Marcel R. Cyr]

Originally Posted by badair

The answer is contained within this doc

http://www.steeldoor.org/res/118.pdf

Barry;

I think you have just closed the Poll.

I know I am one of the four on the 90 min. and was hoping to see how many were going to vote for the 120.

Oh well.

Marcel

[Barry Adair]

Originally Posted by mcyr

Barry;

I think you have just closed the Poll.

I know I am one of the four on the 90 min. and was hoping to see how many were going to vote for the 120.

Oh well.

Marcel

My poll says badair waits 72 hours before posting how about yours

[Mike Hazelwood]

Just a curious question....Why is the door only required to be 1.5 hour rated and the walls are 2 hour rated? A chain is as strong as its weakest link.

[Marcel R. Cyr]

Originally Posted by mhazelwood

Just a curious question....Why is the door only required to be 1.5 hour rated and the walls are 2 hour rated? A chain is as strong as its weakest link.

This might help a little.

It is common for a fire door to have a fire protection rating lower than the wall fire resistance rating in which it is installed. This is justified in part by the fact that, under normal conditions of use, the potential fire exposure in the vicinity of a door opening is decreased, since there will usually be a clear space on both sides of the opening for traffic purposes. Since wall assemblies are put together at the site, their uniformity is not as certain as a fire door assembly that is factory assembled (e.g., undesigned penetrations tend to show up in wall assemblies). For this reason, any factor of safety that is tacitly called for in a wall assembly requirement should exceed that of a door assembly. If the opening is not used, combustibles could be piled against the door, and the assumed enclosure protection might not be maintained. I these instances, ratings for the openings should be equivalent to the rating of the wall, or precautions should be taken to prevent storage of combustibles against the doors.

Ref. NFPA 252 Standard Methods of Fire Tests of Door Assemblies

Marcel