Medical Gas Piping installed in a multi-trade rack

  • Wednesday, August 19, 2020 8:43 PM
    Message # 9177665

    I am currently involved in a hospital project where the medical gas piping is installed in a multi-trade rack, i.e. with ductwork, water piping, etc. The rack itself has been structurally designed and calculated so that it is considered an extension of the structure. The piping within the rack is supported/hung as required for medical gases and the piping is brazed in the field where the racks connect. The AHJ is claiming that this is not allowed citing a "safety concern". (The only section he cites against this is NFPA 101, the AHJ can make any decision.) I personally cannot identify the safety concern but was hoping that some one might enlighten me on what I am missing here.

    Should medical gas systems not be in a multi-trade rack? 

  • Wednesday, August 19, 2020 10:47 PM
    Reply # 9177865 on 9177665
    Deleted user

    I'm not aware of a NFPA 99 medical gas code that prohibits supporting medical gas tubing and other utilities such as water or electrical conduit using the same trapeze hanger.  



    NFPA 99, 2018 (WI uses 2012 edition & I think it has the same language) Piping shall be supported from the building structure.

  • Thursday, August 20, 2020 7:59 AM
    Reply # 9178734 on 9177665

    It should not be any concern regarding safety as I see it, the code allows the medical gas system pipe to be in the same trench, why should it not be allowed to be installed in an structure designed for it and other systems? Medical gas piping shall be permitted to be installed in the same service trench or tunnel with fuel gas lines, fuel oil lines, electrical lines, steam lines, and similar utilities, provided that the space is ventilated (naturally or mechanically) and the ambient temperature around the medical gas piping is limited to 54°C (130°F) maximum. Piping shall be supported from the building structure.

  • Friday, August 21, 2020 5:48 AM
    Reply # 9181224 on 9177665

    If the piping meets the requirements of Pipe Support, it should be ok.

    I guess the question should be asked; who designated the multi-track and extension of the building structure?

    If you have documentation showing that, and the Hangers and Supports used to attached to the Multi-Track comply with, more specifically the MSS SP-58 (see attached) this should be acceptable.

    1 file
    Last modified: Friday, August 21, 2020 5:49 AM | Anonymous

16339 Kranker Drive, Stilwell, KS 66085