Medical Gas Professional Healthcare Organization

Leading through education, we save lives


Instrument Air Zone Valve.

  • Thursday, July 20, 2017 1:41 PM
    Message # 4986748
    Mathis Carlson (Administrator)

    I have an instrument air line running from a hospital into the MOB Endo area. It's only use point in the endo area is the scope drying cabinet. It comes off the service valve and connects directly to the cabinet with copper. No zone valve installed. 
    We sited the lack of zone valve and a special instalation in accordance with:


    5.1.4.8.7.1 All gas delivery columns, hose reels, ceiling tracks,

    control panels, pendants, booms, or other special installations

    shall be located downstream of the zone valve.


    The engineer of record has taken exception to the zone valve requirement.
    Thoughts?

  • Thursday, July 20, 2017 2:55 PM
    Reply # 4986875 on 4986748

    If it terminates as a "station outlet," then I would ask the engineer to reference the code supporting his exception.

     

    NFPA 99, 2012 explicitly defines instrument air as a medical support gas.

     

    3.3.84 Instrument Air. For the purposes of this code, instrument air is air intended for the powering of medical devices unrelated to human respiration (e.g., surgical tools, ceiling arms). Medical air and instrument air are distinct systems for mutually exclusive applications. Instrument air is a medical support gas that falls under the general requirements for medical gases.

     

     

    Furthermore, NFPA 99, 2012 is explicit that the requirements apply to all medical gases and medical support gases.

     

    5.1.1.2* Where the terms medical gas or medical support gas occur, the provisions shall apply to all piped systems for oxygen, nitrous oxide, medical air, carbon dioxide, helium, nitrogen, instrument air, and mixtures thereof. Wherever the name of a specific gas service occurs, the provision shall apply only to that gas.

     

    So, the use point in question would require a zone valve compliant with 5.1.4.8 through 5.1.4.8.8:

     

    5.1.4.8 Zone Valves. All station outlets/inlets shall be supplied through a zone valve as follows:

     

     

     

     

     

     

     

    Last modified: Thursday, July 20, 2017 3:29 PM | Luke Miller
  • Thursday, July 20, 2017 3:34 PM
    Reply # 4986914 on 4986748
    Mathis Carlson (Administrator)

    His first justification is that the Instrument Air is not a station outlet, because in the definitions a station outlet is where a user connects and disconnects a device. Since this is never disconnected, it is not a station outlet. He compared it to the boom breaks not being connected to a station outlet.


    Second he referenced that in 5.1.8.4.7 it calls for zone valves to be installed  for vital life-support areas, critical care areas, and anesthetizing locations.
    So, because scope cleaning rooms or support gas locations are not listed, he does not have to have a zone valve in those areas. 

  • Thursday, July 20, 2017 3:49 PM
    Reply # 4986936 on 4986748

    In regards to his first point, I would ask if he considers this a "special installation?"

     

    5.1.4.8.7.1 All gas delivery columns, hose reels, ceiling tracks, control panels, pendants, booms, or other special installations shall be located downstream of the zone valve.

     

    As for his second point, my opinion is that he's misinterpreting the code.  5.1.4.8 is explicit that all outlets (regardless of area) must be controlled by a zone valve. 

     

    My interpretation is that 5.1.4.8.7 is not the requirement for the zone valve itself (that's 5.1.4.8), rather it's the requirement for the location ("immediately outside" and "readily accessible") of the zone valves controlling these areas.

    Last modified: Thursday, July 20, 2017 3:59 PM | Luke Miller
  • Friday, July 21, 2017 12:24 PM
    Reply # 4988425 on 4986748

     I'm not familiar with the cabinet but you may want to consider it plant air?  If it's connected directly to the cabinet and there is no place for someone to connect a hose or disconnected a hose but is only passing gas through the cabinet.  I would consider plant air. How do they activate the gas when they need it? 

  • Friday, July 21, 2017 12:27 PM
    Reply # 4988427 on 4986748
    Al Moon (Administrator)

    I agree with you both. It requires a zone valve box. At times, we have the hard job of providing patient and public safety. When the surgeon cannot run his tools in the middle of brain or heart surgery, because the clear room staff had an accident with the Nitrogen or IA system and their was no fast way the shutdown that area. The News Print will be bad.

  • Friday, July 21, 2017 1:09 PM
    Reply # 4988479 on 4988425
    Mathis Carlson (Administrator)
    Don Holden wrote:

     I'm not familiar with the cabinet but you may want to consider it plant air?  If it's connected directly to the cabinet and there is no place for someone to connect a hose or disconnected a hose but is only passing gas through the cabinet.  I would consider plant air. How do they activate the gas when they need it? 


    If they had plant air, or equipment air available, I would say that is an excellent option. However, because they are using IAir under the usage of drying instruments before further processing, IAir requirements apply such as Zone Valves etc. 

  • Friday, July 21, 2017 1:09 PM
    Reply # 4988480 on 4988427
    Mathis Carlson (Administrator)
    Al Moon wrote:

    I agree with you both. It requires a zone valve box. At times, we have the hard job of providing patient and public safety. When the surgeon cannot run his tools in the middle of brain or heart surgery, because the clear room staff had an accident with the Nitrogen or IA system and their was no fast way the shutdown that area. The News Print will be bad.


    I usually like to avoid that bad news print!

16339 Kranker Drive, Stilwell, KS 66085

mgpho@me.com