The table below can be used as an indication of recommended air changing rates in some common rooms and buildings.
Building / Room Air Change Rates- n - (AC/Hr.)
All spaces in general min 4
Attic spaces for cooling 12 - 15
Auditoriums 8 - 15
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
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 hotels 5
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 Office 8 - 12
Mills, paper 15 - 20
Mills, textile general buildings 4
Mills, textile dyehouses 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 15 - 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 (1/n)
V = volume of room (ft3, m3)
Example - Fresh Air Supply to Public Library
The fresh air supply to a public library with volume 1000 m3 can be calculated as
Q = 4 (1/h) 1000 (m3)
= 4000 m3/h
