Air Change Rates for typical Rooms and Buildings

Fresh air requirements - recommended air change rates - ACH - for some typical rooms and buildings - auditoriums, kitchens, churches and more

The volume of fresh air (make up air) required for proper ventilation is determined of the size and use of the space.

air change rate

The table below indicates recommended air change rates (air changes per hour) in some common types of rooms and buildings:

Building / RoomAir Change Rates
- n -
(1/h, h-1)
All spaces in general min 4
Attic spaces for cooling 12 - 15
Auditoriums 8 - 15
Bakeries 20
Banks 4 - 10
Barber Shops 6 - 10
Bars 20 - 30
Beauty Shops 6 - 10
Boiler rooms 15 - 20
Bowling Alleys 10 - 15
Cafeterias 12 - 15
Churches 8 - 15
Club rooms 12
Clubhouses 20 - 30
Cocktail Lounges 20 - 30
Computer Rooms 15 - 20
Court Houses 4 - 10
Dental Centers 8 - 12
Department Stores 6 - 10
Dining Halls 12 -15
Dining rooms (restaurants) 12
Dress Shops 6 - 10
Drug Shops 6 - 10
Engine rooms 4 - 6
Factory buildings, ordinary 2 - 4
Factory buildings, fumes and moisture 10 - 15
Fire Stations 4 - 10
Foundries 15 - 20
Galvanizing plants 20 - 30
Garages repair 20 - 30
Garages storage 4 - 6
Homes, night cooling 10 - 18
Jewelry shops 6 - 10
Kitchens 15 - 60
Laundries 10 - 15
Libraries, public 4
Lunch Rooms 12 -15
Luncheonettes 12 -15
Nightclubs 20 - 30
Malls 6 - 10
Medical Centers 8 - 12
Medical Clinics 8 - 12
Medical Offices 8 - 12
Mills, paper 15 - 20
Mills, textile general buildings 4
Mills, textile dye houses 15 - 20
Municipal Buildings 4 - 10
Museums 12 -15
Offices, public 3
Offices, private 4
Police Stations 4 - 10
Post Offices 4 - 10
Precision Manufacturing 10 - 50
Pump rooms 5
Restaurants 8 - 12
Retail 6 - 10
School Classrooms 4 - 12
Shoe Shops 6 - 10
Shopping Centers 6 - 10
Shops, machine 5
Shops, paint 15 - 20
Shops, woodworking 5
Substation, electric 5 - 10
Supermarkets 4 - 10
Town Halls 4 - 10
Taverns 20 - 30
Theaters 8 - 15
Turbine rooms, electric 5 - 10
Warehouses 2
Waiting rooms, public 4

Note that in many cases local regulations and codes will govern the ventilation requirements.

The fresh air supply to a room can be calculated as

q = n V         (1)

where

q = fresh air supply (ft3/h, m3/h)

n = air change rate (h-1)

V = volume of room (ft3, m3)

Example - Fresh Air Supply to a Public Library

The fresh air supply to a public library with volume 1000 m3 can be calculated as

Q = (4 h-1) (1000 m3)

    = 4000 m3/h

Air Volume Calculator

No. of Changes per Hour (h-1)

Room Volume (m3, ft3)

Air Change Out Frequency in minutes

Air Change Out Frequency in minutes can be calculated as 

nm = 60 / n     (2)

where

nm = Air Change Out Frequency (minutes)

Related Topics

  • Ventilation - Systems for ventilation and air handling - air change rates, ducts and pressure drops, charts and diagrams and more

Related Documents

Key Words

Search the Engineering ToolBox

- "the most efficient way to navigate the Engineering ToolBox!"

Engineering ToolBox - SketchUp Edition - Online 3D modeling!

3D Engineering ToolBox - draw and model technical applications

Engineering ToolBox - SketchUp Edition - add standard and customized parametric components - like flange beams, lumbers, piping and more - to your SketchUp model - enabled for use with the amazing, fun and free SketchUp Make and SketchUp Pro. Add from the Sketchup Extension Warehouse!

Translate the Engineering ToolBox!
About the Engineering ToolBox!

close