Air Changes
Air Changes per hour
The air changes up to eight an hour provide for removing contamination normally caused by human occupants. The higher rates of air changes provide for removing heat and steam in temperate zones. In hot climates the air changes per hour should be at least doubled.
Where smoking occurs allow twice the number of air changes.
The Table below gives a guide to the number of air changes per hour generally accepted in ventilation.
| SITUATION | AIR CHANGES PER HOUR |
| Assembly Halls | 4 – 6 |
| Bakeries | 20 - 30 |
| Banks | 2 - 4 |
| Billiard Rooms | 6 - 8 |
| Boiler House | 20 - 30 |
| Cafes & Coffee Bars | 10 - 12 |
| Canteens | 4 - 6 |
| Churches | 1/2 - 1 |
| Cinemas | 10 - 15 |
| Club Rooms | 8 - 10 |
| Dance Halls | 6 - 8 |
| Dye Works | 20 - 30 |
| Engine Rooms | 20 - 30 |
| Ensuites | 15 - 20 |
| Factories (Workshops) | 6 - 10 |
| Foundries | 20 - 30 |
| Garages | 6 - 8 |
| Hospitals (General Wards) | 4 - 6 |
| Hotel Bars | 4 - 6 |
| Kitchens (Commercial) | 15 - 20 |
| Kitchens (Domestic) | 10 - 15 |
| Laboratories | 4 - 6 |
| Lavatories | 10 - 15 |
| Laundries | 20 - 30 |
| Machine Shops | 6 - 10 |
| Offices | 4 - 6 |
| Paint Shops | 30 - 60 |
| Photographic Darkrooms | 10 - 15 |
| Pig Houses | 6 - 10 |
| Poultry Houses | 6 - 10 |
| Residences | 1 - 2 |
| Restaurants | 6 - 10 |
| School Classrooms | 2 - 3 |
| Swimming Baths | 20 - 30 |