Exhaust Fan Calculator
Check the number of Exhaust fans required in your premises.
Note : Unit of measurement - Meter
Average Air Changes Per Hour (ACH) Table by Premises
To ensure optimal ventilation in your industrial space, it's crucial to know the recommended air changes per hour (ACH) based on the type of premises. Below, you'll find a table that outlines the average ACH required for various industrial environments. This information will help you determine the appropriate CFM and select the right exhaust fan for effective airflow and air quality maintenance.
Types of Premises | Air Change in Hour (ACH) |
---|---|
All spaces in general | min 4 |
Assembly halls | 4 - 6 |
Attic spaces for cooling | 12 - 15 |
Public Auditoriums | 8 - 15 |
Bakeries | 20 - 30 |
Banks/Building Societies | 4 - 8 |
Bars | 20 - 30 |
Bathrooms | 6 - 10 |
Bedrooms | 5 - 6 |
Pool Halls | 6 - 8 |
Boiler Rooms | 15 - 30 |
Bowling Alleys | 10 - 15 |
Cafeterias | 12 - 15 |
Canteens | 8 - 12 |
Basement | 3 - 10 |
Changing Rooms Main area | 6 - 10 |
Changing Rooms Shower area | 15 - 20 |
Churches | 8 - 15 |
Cinemas and theatres * | 10 - 15 |
Classrooms | 6 - 20 |
Clubhouses | 20 - 30 |
Cocktail Lounges | 20 - 30 |
Compressor rooms | 10 - 20 |
Computer Rooms | 15 - 20 |
Conference rooms | 8 - 12 |
Copy Room | 10 - 12 |
Court Houses | 4 - 10 |
Dairies | 8 - 10 |
Dance halls | 12 minimum |
Dental surgeries | 12 - 15 |
Large Shops | 6 - 10 |
Dining Halls | 12 -15 |
Restaurant Dining Area | 12 |
Chemists | 6 - 10 |
Dye works | 20 - 30 |
Electroplating shops | 10 - 12 |
Engine rooms | 15 - 30 |
Factories and workshops | 8 - 10 |
Factory buildings, with fumes or moisture | 10 - 15 |
Fire Stations | 4 - 10 |
Food Staging Area | 10 - 12 |
Foyer - public buildings | 15 - 20 |
Metal Workshop | 15 - 20 |
Galvanizing plants | 20 - 30 |
Garages | 6 - 8 |
Garages repair | 20 - 30 |
Garages storage | 4 - 6 |
Greenhouses | 25 - 60 |
Gymnasiums | 6 minimum |
Hairdressing salons | 10 - 15 |
Hospital rooms | 4 - 6 |
Hospitals - sterilising | 15 - 25 |
Hospitals - wards | 6 - 8 |
Types of Premises | Air Change in Hour (ACH) |
---|---|
Kitchens - commercial | 30 minimum |
Kitchens - domestic | 15 - 20 |
Laboratories | 6 - 15 |
Laundrettes | 10 - 15 |
Laundry Room | 8 - 10 |
Lavatories | 6 - 15 |
Lecture theatres | 5 - 8 |
Libraries | 3 - 5 |
Living rooms | 6 - 8 |
Lunch Rooms | 12 -15 |
Machine shops | 6 - 12 |
Malls | 6 - 10 |
Medical Offices | 8 - 12 |
Mills, paper | 15 - 20 |
Mills, textile dye houses | 15 - 20 |
Mills, textile general buildings | 4 minimum |
Municipal Buildings | 4 - 10 |
Museums | 12 -15 |
Mushroom houses | 6 - 10 |
Nightclubs | 20 - 30 |
Offices | 6 - 10 |
Offices, private | 4 minimum |
Offices, public | 3 minimum |
Paint shops (not cellulose) | 10 - 20 |
Photo & X-ray darkrooms | 10 - 15 |
Pump rooms | 5 minimum |
Recording control rooms | 15 - 25 |
Recording studios | 10 - 12 |
Restaurants | 8 - 12 |
Retail Outlets | 6 - 10 |
School Classrooms | 4 - 12 |
Shopping Centers | 6 - 10 |
Shops and supermarkets | 8 - 15 |
Shops, paint | 15 - 20 |
Shops, woodworking | 5 minimum |
Shower baths | 15 - 20 |
Smoking Room | 13 - 15 |
Squash courts | 4 minimum |
Stores & warehouses | 3 - 6 |
Substation, electric | 5 - 10 |
Supermarkets | 4 - 10 |
Swimming pools | 20 - 30 |
Taverns | 20 - 30 |
Theaters | 8 - 15 |
Toilets 6 - 10 | 6 - 10 |
Town Halls | 4 - 10 |
Transformer rooms | 10 - 30 |
Turbine rooms, electric | 5 - 10 |
Utility rooms | 15 - 20 |
Waiting rooms - public buildings | 4 minimum |
Warehouses | 6 - 30 |
Welding shops | 15 - 30 |
FAQs
CFM = (Room Volume in Cubic Feet × ACH) / 60
where:
ACH — Air change per hour.
The unit of airflow is CFM, which means cubic feet per minute.