MINIMUM RATE OF AIR CHANGE PER HOUR
Table 1
AVERAGE GENERAL VENTILATION
Classification of establishments Minimum rate of air
change per hour
Food and beverages
______________________________________________________________________________
Slaughterhouses and drysalting 2
______________________________________________________________________________
Mineral oil and fats factories 3
______________________________________________________________________________
Sausage and sausage casing manufacturing 2
______________________________________________________________________________
Poultry processing 2
______________________________________________________________________________
Milk concentrate manufacturing 2
______________________________________________________________________________
Fish processing 2
______________________________________________________________________________
Preparation and canning of fruit and vegetables 2
______________________________________________________________________________
Biscuit manufacturing 2
______________________________________________________________________________
Bakeries 2
______________________________________________________________________________
Confectioneries 2
______________________________________________________________________________
Vegetable oil mills 2
______________________________________________________________________________
Distilleries 2
______________________________________________________________________________
Breweries (Beer breweries) 2
______________________________________________________________________________
Wine manufacturing 2
Tobacco products
______________________________________________________________________________
Leaf-tobacco processing 2
______________________________________________________________________________
Tobacco products manufacturing 2
Rubber
______________________________________________________________________________
Rubber footwear manufacturing 3
______________________________________________________________________________
Tire and tube manufacturing 3
______________________________________________________________________________
Other rubber industries 3
Leather
______________________________________________________________________________
Tanneries 3
______________________________________________________________________________
Shoe factories 2
Textiles
______________________________________________________________________________
Cotton yarn and cloth mills 2
______________________________________________________________________________
Wool yarn mills 2
______________________________________________________________________________
Wool cloth mills 2
______________________________________________________________________________
Synthetic textile mills 2
______________________________________________________________________________
Fiber preparation mills 5
______________________________________________________________________________
Thread mills 5
______________________________________________________________________________
Cordage and twine industry 5
______________________________________________________________________________
Carpet, mat and rug industry 2
______________________________________________________________________________
Textile dying and finishing 3
______________________________________________________________________________
Linoleum and coated fabrics industry 4
Garages
______________________________________________________________________________
Garage for maintenance and repair 4
______________________________________________________________________________
Garage for parking and storage
- with permanent employees 3
______________________________________________________________________________
- without permanent employees 2
Wood
______________________________________________________________________________
Shingle plants 2
______________________________________________________________________________
Sawmills 2
______________________________________________________________________________
Veneer and plywood mills 2
______________________________________________________________________________
Sash, door and other millwood plants (excluding hardwood
flooring manufacturing) 2
______________________________________________________________________________
Coffin and casket industry 2
______________________________________________________________________________
Wood processing industry 2
Furniture and fixtures
______________________________________________________________________________
Household furniture industry 2
Paper and related products
______________________________________________________________________________
Pulp and paper mills 2
______________________________________________________________________________
Manufacturing of asphalt roofing paper 3
______________________________________________________________________________
Paper box and bag manufacturing 2
Metal products
______________________________________________________________________________
Metal fabricating industries 4
______________________________________________________________________________
Miscellaneous machinery manufacturing 2
______________________________________________________________________________
Electrical appliance manufacturing 2
______________________________________________________________________________
Cell and battery manufacturing 4
Non-metallic products
______________________________________________________________________________
Cement industry 3
______________________________________________________________________________
Lime industry 3
______________________________________________________________________________
Gypsum products manufacturing 3
______________________________________________________________________________
Concrete products manufacturing 2
______________________________________________________________________________
Reinforced concrete industry 2
______________________________________________________________________________
Clay products manufacturing (domestic clay) 2
______________________________________________________________________________
Refractory products manufacturing 4
______________________________________________________________________________
Stone products manufacturing 4
______________________________________________________________________________
Asbestos products manufacturing 6
______________________________________________________________________________
Glass and glass products manufacturing 4
______________________________________________________________________________
Abrasive industry 4
Chemicals
______________________________________________________________________________
Explosives and ammunition manufacturing 3
______________________________________________________________________________
Mixed fertilizers manufacturing 2
______________________________________________________________________________
Plastics and synthetic resins industry 3
______________________________________________________________________________
Pharmaceuticals and medical products industry 2
______________________________________________________________________________
Paints and varnish industry 4
______________________________________________________________________________
Maintenance products manufacturing 3
______________________________________________________________________________
Industrial chemical products manufacturing 2
Warehouses: See Table III of this Schedule.
Any other class of establishment not appearing in this
Table or in Table II of this Schedule 1
The number of air changes per hour listed in this Table may be converted into cfm/ft2 by using the following formula:
ft3/min.=Air change/hour × [12ft + height of work level in feet (ref. main floor)]
_____ _______________
ft2 60 min./hour
or to m3/h/m2 by using the following formula:
m3/h = Air change/hour × [3.6m + height of work level in metres (ref. main floor)]
___
m2
Table 2
RATE OF AIR CHANGE PER HOUR FOR CERTAIN CLASSES OF ESTABLISHMENT
Classification Total ventilation area Fresh air
of
establishment ________________________________________________ Relative pressure
Unrefrigerated Refrigerated Refrigerated or
spaces spaces unrefrigerated
(l./s./pers.) (l./s./pers.) spaces
(l./s./pers.)
Commercial 9.4 not 2.4 negative pressure
and industrial applicable not exceeding
laundry 5 Pa
Office 7.1 45 2.4 not applicable
Laboratory* 7.1 45 2.4 negative pressure
not exceeding
5 Pa
Where gases, fumes, vapours, dusts or are mists emitted in an establishment listed in this Table, the minimum rates of air change per hour must be increased so that the standards prescribed in Schedule 1 are complied with.
* To compute total ventilation air and fresh air, the occupancy rate must be one person per 10 m2 for laundries and offices and one person per 5 m2 for laboratories.
Table 3
VENTILATION IN WAREHOUSES WHERE INTERNAL COMBUSTION VEHICLES ARE OPERATED
The ventilation rate per vehicle must be computed as follows:
Q = K × (U/50 %) × (P/45kW) × [2 - (V/4250m3)]
where:
Q = air flow in m3/h prescribed per vehicle
K = ventilation constant, namely 8 500 m3/h per propane or diesel-powered vehicle, 13,500 m3/h per gas-powered vehicle
P = power of the engine in kilowatts
V = volume of space available in m3 per vehicle
U = percentage (%) of use of the vehicle during a work shift.
Notes:
(1) if the percentage (U) of use of the vehicle or the power (P) of the engine is less than 50% or 45 KW respectively, these factors must be omitted in the formula which then must read as follows:
Q = K × [2 - (V/4250m3)]
(2) for the purposes of applying this Table, the volume of space available is equal to the total volume of the warehouse minus the volume occupied by the merchandise;
(3) if the volume available exceeds 4,250 m3, the formula does not apply and the minimum air supply is 8,500 m3/h per propane or diesel-powered vehicle and 13,500 m3/h per gas-powered vehicle.