Air Change Rates

Building / Room Air Change Rates
– n –
(1/hr)
All Spaces in general min 4
Attic spaces for cooling 12 – 15
Auditoriums 8 – 15
Bakery 20 – 60
Banks 4 – 10
Barber Shops 6 ? 10
Bars 20 – 30
Beauty Shops 6 ? 10
Boiler rooms 20 ? 60
Bowling Alleys 10 ? 15
Cafeterias 12 ? 20
Churches 15 ? 30
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
Dormitories 7 ? 12
Dress Shops 6 – 10
Drug Shops 6 – 10
Engine rooms 12 ? 30
Factory buildings, ordinary 6 ? 15
Factory buildings, fumes and moisture 10 ? 15
Fire Stations 4 – 10
Foundries 15 – 30
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 20 – 60
Libraries, public 15 – 30
Locker Rooms 4 ? 15
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 7 ? 12
Mills, textile dyehouses 15 – 20
Municipal Buildings 4 ? 10
Museums 12 ?15
Offices, public 5 ? 12
Offices, private 5 ? 12
Packing Houses 12 ? 20
Plating Rooms 12 – 60
Police Stations 4 ? 10
Post Offices 4 ? 10
Precision Manufacturing 15 – 50
Printing Shops 6- 12
Pump rooms 5
Restaurants 8 – 20
Rest Rooms 6 ? 12
Retail 6 ? 10
School Classrooms 6 ? 12
Shoe Shops 6 ? 10
Shopping Centers 6 ? 10
Shops, machine 6 ? 12
Shops, paint 15 – 20
Shops, woodworking 5
Substation, electric 5 ? 10
Supermarkets 4 ? 10
Town Halls 4 ? 10
Taverns 20 – 30
Theaters 8 ? 20
Transformer Rooms 12 ? 60
Turbine rooms, electric 5 ? 10
Warehouses 6 ? 12
Waiting rooms, public 4
Welding Shop 12 – 60

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 Woodworking Shop

The fresh air supply to a wood working shop with volume 1000 m3 can be calculated as

Q = 5 (1/h) 1000 (m3)

= 5000 m3/h