Outdoor Supply Air Rates
The rates of outdoor make-up or supply air in the table below can be used as a guideline in the design of ventilation systems.
Air Shifts
Air shift is the number of times the air in a room is replaced by supply air per hour and can be expressed as
n = q / V (1)
where
n = air shifts (1/h)
q = supply air to the room (m3 /h)
V = room volume (m3 )
Example - Air Shifts
The air supply to a room with volume 10 m 3 is 5 m3 /h . The air shifts can be calculated
n = ( 5 m3 /h ) / ( 10 m3 )
= 0.5 1/h
Recommended Supply Air to some typical Rooms
Type of Building and Room | Air Shifts - n - (1/h) | Supply Air flow ( l/s per m2 floor area) | Supply Air Flow (l/s) | |
---|---|---|---|---|
Animals | Sheep | 3 per animal | ||
Horses | 40 per animal | |||
Hens | 3 per animal | |||
Cows | 100 per animal | |||
Chickens | 2 per animal | |||
Pigs, sow | 60 per animal | |||
Piglet | 15 per animal | |||
Apartments | 15 per person | |||
Assembly halls | 5 - 10 | 10 - 15 per person | ||
Auditoriums | 10 - 15 per person | |||
Bakeries | Production | 8 | ||
Pastry room | 6 | |||
Banks | Service | 2 - 3 | ||
Archive | 1 | |||
Staff | 2 - 3 | |||
Baths | 5 - 8 | 15 | ||
Barber Shops | 10 - 15 per person | |||
Bars | 15 - 20 per person | |||
Beauty Shops | 10 - 15 per person | |||
Bowling Alleys | 10 - 15 per person | |||
Cafeterias | 4 | 10 - 15 per person | ||
Cinemas/Theaters | 5 - 10 | 7 - 10 per person | ||
Chemist's shops | Sterile room | 15 | ||
Laboratory | 15 | |||
Packing room | 4 | |||
Store | 1 | |||
Churches | 2 | 10 per person | ||
Clubhouses | 15 - 20 per person | |||
Cocktail Lounges | 15 - 20 per person | |||
Computer Rooms | 10 - 15 per person | |||
Court Houses | 10 - 15 per person | |||
Dance halls | 15 - 20 per person | |||
Dental Clinics, Offices | 10 - 15 per person | |||
Department Stores (cfm/Sq.Ft) | 0.3 | |||
Dining Halls | 10 - 15 per person | |||
Drug Shop | 10 - 15 per person | |||
Engine rooms | 4 | |||
Exhibition halls | 10 - 20 | |||
Fire Stations | 10 - 15 per person | |||
Garages | 5 - 6 | > 1 | ||
Hospitals | General | 15 per person | ||
Therapy | 9 | |||
Operating theater | 14 | |||
Autopsy | 9 | |||
Hotels | Reception | 15 - 20 per person | ||
Room | 3 | |||
Industries | Factory | 10 - 20 per person | ||
Carpenter work shop | 2 - 5 | |||
Car repair shop | 4 | |||
Car repair shop, exhaust outlet | 60 - 80 per car | |||
Mechanical work shop | 3 - 4 | |||
Welding | 12 - 15 | |||
Assembly | 4 - 5 | |||
Jails | 10 - 15 per person | |||
Jewelry Shop | 10 - 15 per person | |||
Libraries | 10 - 15 per person | |||
Lift Shaft (Lift Car) | 8 - 10 | |||
Lunch Rooms, Luncheonettes | 10 - 15 per person | |||
Municipal Buildings | 10 - 15 per person | |||
Museums | 10 - 15 per person | |||
Smithies |
6 - 7 |
|||
Kitchens | Small | 20 - 40 | ||
Large | 10 - 20 | |||
< 7 m2 | 15 | |||
> 7 m2 | 20 | |||
Industrial in general | 25 - 30 | |||
Gas ovens | 550/m2outside wall | |||
Electric ovens | 300/m2outside wall | |||
Grill table | 400/m2outside wall | |||
Frying pan | 300 | |||
Boiling pan 100 l | 100 | |||
Boiling pan 200 l | 200 | |||
Coffee machine | 60 | |||
Refrigerated cabinet | 7 - 10 | |||
Cooling and freezer room | 0.3 - 0.5 | |||
Store | 2 - 4 | |||
Laundries | 10 - 15 | |||
Lavatories | 5 - 10 | 10 | ||
Night Clubs | 15 - 25 per person | |||
Malls | 10 - 15 per person | |||
Motels | 15 - 20 per person | |||
Offices | Module | 3 - 8 | 10 - 20 per person | |
Landscape | 10 - 20 per person | |||
Conference room | 15 - 30 per person | |||
Lecture room | 10 - 20 per person | |||
Dining hall | 15 - 25 per person | |||
Staff, changing clothes | 8 - 12 | |||
Dining room | 8 - 10 | |||
Resting room | 15 per person | |||
Police Stations | 10 - 15 per person | |||
Post Offices | 10 - 15 per person | |||
Precision Manufacturing | 10 - 15 per person | |||
Restaurants | 5 - 10 | 10 | 10 - 15 per person | |
Retail Stores (cfm/Sq.Ft) | 0.3 | |||
Schools | Classroom | 4 - 5 | 10 - 15 per person | |
Shops | 10 - 15 per person | |||
Shopping Centers | 10 - 15 per person | |||
Sports halls | 3 - 4 | |||
Supermarkets | 10 per person | |||
Swimming pools | 5 - 10 | |||
Taverns | 10 - 15 per person | |||
Town Halls | 10 - 15 per person |
- 1 dm3 (liter)/s = 10-3 m3 /s = 3.6 m3 /h = 0.03532 ft3 /s = 2.1189 ft3 /min (cfm) = 13.200 Imp.gal (UK)/min = 15.852 gal (US)/min = 792 Imp. gal (UK)/h
Smoking or Not Smoking versus Recommended Supply Air
Smoking has a dramatic impact on required make up air ( Chartered Institution of Building Service Engineers , CIBSE Guide B2):
Level of Smoking | Proportion of occupants that smoke (%) | Supply Air (liter/s person) |
---|---|---|
No smoking | 0 | 8 |
Some smoking | 25 | 16 |
Heavy smoking | 45 | 24 |
Very heavy smoking | 75 | 36 |
Recommended Residential Air Ventilation
Recommended outdoor air supply according ASHRAE 62.2:
Air Flow (cfm) | |||||
---|---|---|---|---|---|
Floor Area (ft2) | Bedrooms | ||||
0 - 1 | 2 - 3 | 4 - 5 | 6 - 7 | > 7 | |
< 1500 | 30 | 45 | 60 | 75 | 90 |
1501 - 3000 | 45 | 60 | 75 | 90 | 105 |
3001 - 4500 | 60 | 75 | 90 | 105 | 120 |
4501 - 6000 | 75 | 90 | 105 | 120 | 135 |
6001 - 7500 | 90 | 105 | 120 | 135 | 150 |
> 7500 | 105 | 120 | 135 | 150 | 165 |
Related Topics
• Ventilation Systems
Design of systems for ventilation and air handling - air change rates, ducts and pressure drops, charts and diagrams and more.
Related Documents
Air Change Rate
Calculate air change rates - equations in imperial and SI units.
Air Change Rates in typical Rooms and Buildings
Fresh air (make up air) rquirements - or recommended air change rates (ACH) for typical rooms and buildings like auditoriums, kitchens, churches and more.
Heat Recovery Efficiency
Classification of heat recovery efficiencies - temperature efficiency, moisture efficiency and enthalpy efficiency - online heat exchanger efficiency calculator.
Outdoor Makeup Air
Acceptable indoor air quality and required make up air.
Pollution Concentration in Rooms
Concentration of a pollution in a limited space as a room depends on the amount of polluted material spread in the room, supply of fresh air, outlets positions and construction, principles used for supply and outlet from the space.