At what size pipe would a fire collar be required? I cannot find a code reference in LSC chapter 8 or IFC. I did find some commentary from the ICC but it only stated that anything greater than 3 inches, check the system.
Fire stop method?
Seems like based on type of pipe and per manufacture of fire stop method
The requirements like in Section 126.96.36.199 Firestop Systems and Devices Required of the 2018 NFPA 101 are performance specification as most of the code is not prescriptive. The code does not preclude the use of 'fire collars' for specific sizes of pipe. In accordance with Section 188.8.131.52.1, penetration for pipes of any size that pass through a wall, floor, or floor/ceiling assembly constructed as a fire barrier must be protected by a firestop system or device.
Therefore, the code always allows good sense and judgement to chose an appropriate firestop system to meet the NFPA 101's performance requirements.
I find that Volume 2 of the Underwriters Laboratories (UL) Fire Resistance Directory the best source of information. UL classifies such devices and systems with respect to installation in a wall only, installation in a floor only, or installation in a wall or floor.
Commonly tested devices for firestopping the various penetrations are:
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