TecKnows

Air Change Rates Calculation

The table below indicates air change rates (air changes per hour) in common types of rooms and buildings. All spaces in general min 4
Assembly halls 4 – 6
Attic spaces for cooling 12 – 15
Auditoriums 8 – 15
Bakeries 20 – 30
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
Classrooms 6 – 20
Club rooms 12
Clubhouses 20 – 30
Cocktail Lounges 20 – 30
Computer Rooms 15 – 20
Court Houses 4 – 10
Dance halls 6 – 9
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
Hospital rooms 4 – 6
Jewelry shops 6 – 10
Kitchens 15 – 60
Laundries 10 – 15
Libraries, public 4
Lunch Rooms 12 -15
Luncheonettes 12 -15
Nightclubs 20 – 30
Machine shops 6 – 12
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
Photo dark rooms 10 – 15
Pig houses 6 – 10
Police Stations 4 – 10
Post Offices 4 – 10
Poultry houses 6 – 10
Precision Manufacturing 10 – 50
Pump rooms 5
Residences 1 – 2
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
Swimming pools 20 – 30
Town Halls 4 – 10
Taverns 20 – 30
Theaters 8 – 15
Transformer rooms 10 – 30
Turbine rooms, electric 5 – 10
Warehouses 2
Waiting rooms, public 4
Warehouses 6 – 30
Be aware of local regulations and codes.
Fresh air supply – make up air – to a room based on the table above 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

Disclaimer: As obtained from the Internet