Advertisement
If you have a new account but are having problems posting or verifying your account, please email us on hello@boards.ie for help. Thanks :)
Hello all! Please ensure that you are posting a new thread or question in the appropriate forum. The Feedback forum is overwhelmed with questions that are having to be moved elsewhere. If you need help to verify your account contact hello@boards.ie
Hi there,
There is an issue with role permissions that is being worked on at the moment.
If you are having trouble with access or permissions on regional forums please post here to get access: https://www.boards.ie/discussion/2058365403/you-do-not-have-permission-for-that#latest

Air Change Rates

  • 16-02-2009 1:48pm
    #1
    my_willy
    Closed Accounts Posts: 1 ✭


    Hey

    Does anyone know the equation for finding out the air change rates per hour using room volume and occupation density.??

    Sound


Comments

  • #2
    murfie
    Registered Users, Registered Users 2 Posts: 768 ✭✭✭murfie


    Typical air change rates can be found here, http://www.engineeringtoolbox.com/air-change-rate-room-d_867.html , but to calculate your Air change rate you would need to know the capacity of the fans or vents allowing air into the room. You will get the CFH and divide it by the volume of the room.


  • #3
    ze4400
    Registered Users, Registered Users 2 Posts: 32 ✭ze4400


    my_willy wrote: »
    Hey

    Does anyone know the equation for finding out the air change rates per hour using room volume and occupation density.??

    Sound

    CIBSE recommends 8 l/s per person for offices. Either count the furniture or base your occupancy on a certain amount of people per square meter of floor area eg. offices = 1/person per 10m2. This will give you a volume flow rate say 8 people = 64l/s or (0.064m3/s). Calculate your room voume (LxWxH) to get a m3. Take for example a room 10m x 8m x 3m = 240m3. Multiply your 0.064m3/s by 3600 to get m3/hr ie. 0.064 x 3600 (secs in an hr) = 230m3/hr. Now divide 230m3/hr by 240m3 = 0.96 air changes per hour. You should also check against CIBSE recommended air change rates for the type of room, ie. an office would be 2 - 3 air changes, use this if the air change calculated from occupant density is lower.


Advertisement