Click
on any of the following links for detailed information.
· OCCUPATIONAL EXPOSURE LIMITS
Ø Design
Ø Maintain
Worker exposure to a hazardous substance must not exceed the exposure limit listed in table 8 to the regulation. The table below is excerpted from table 8, and contains some common hazardous substances and their exposure limits.
|
Chemical name |
8-hour exposure limit |
15-minute exposure limit |
Ceiling |
|
Acetic acid |
10 ppm |
25 ppm |
-- |
|
Acetone |
1,000 ppm |
1,250 ppm |
-- |
|
Ammonia |
25 ppm |
40 ppm |
-- |
|
Carbon black |
3.5 mg/m3 |
7 mg/m3 |
-- |
|
Carbon dioxide |
5,000 ppm |
15,000 ppm |
-- |
|
Carbon monoxide |
50 ppm |
400 ppm |
-- |
|
Ethyl acetate |
400 ppm |
400 ppm |
-- |
|
Formaldehyde |
-- |
-- |
2 ppm |
|
Hydrogen sulfide |
10 ppm |
15 ppm |
-- |
|
Hydroquinone |
2 mg/m3 |
3 mg/m3 |
-- |
|
Isopropyl alcohol |
400 ppm |
500 ppm |
-- |
|
Sulfur dioxide |
5 ppm |
5 ppm |
-- |
(Occupational Health Regulations, 27)
Access routes to work areas where workers may be exposed to oxygen-deficient atmospheres or harmful concentrations of air contaminants must be posted with signs specifying the areas and hazards involved, and the required personal protective equipment. (General Safety Regulations 1986/164, 12)
When workers may be exposed to an oxygen-deficient atmosphere or to harmful concentrations of air contaminants, mechanical means or engineering design must be used to prevent or eliminate those hazardous conditions. (General Safety Regulations 1986/164, 12)
Work places must be adequately ventilated either by natural or mechanical means and excessive air drafts must be avoided.
An employer whose operations produce gases or vapours that may accumulate in hazardous concentrations in work areas must install a ventilation system of capacity sufficient under normal operating conditions to maintain the concentration of contaminants in the atmosphere below the threshold limit values. (General Safety Regulations 1986/164, 27)
Local exhaust
Whenever reasonable practical, contamination must be controlled at the source. When contamination arises from a number of sources not all of which can be controlled by local ventilation at each source, the employer must install a general ventilation system in addition to any local ventilation system.
Whenever an operation produces flammable vapours that may exceed the lower explosive limit, the operation must be provided with its own separate approved exhaust system. General Safety Regulations 1986/164, 27)
Ventilation systems must be designed to provide an amount of fresh air at least equal to the design exhaust capacity of the system. A permanent inlet must be provided for replacement air. (General Safety Regulations 1986/164, 27)
A general ventilation system must be designed so that under normal operations a worker is not located between the source of the contamination and the exhaust pick up, and so that exhausted air does not re-enter the workplace.
When a change in process increases the harmful contaminants in the work environment, the ventilation system must be modified to handle the increase in contaminants. (General Safety Regulations 1986/164, 27)
Ventilation
systems for the control of health hazards must be designed, constructed and
installed in accordance with established engineering principles as published by
the ACGIH Industrial Ventilation: A Manual of Recommended Practice. (Occupational
Health Regulations, 7)
Ventilation systems must be maintained in good order. (General Safety Regulations 1986/164, 27)
Continue by clicking any item
on the menu bar on the left.