Canada Occupational Health and Safety Regulations

10.19 (1) An employee shall be kept free from exposure to a concentration of

• (a) an airborne chemical agent, other than grain dust or airborne chrysotile asbestos, in excess of the value for that chemical agent adopted by the American Conference of Governmental Industrial Hygienists, in its publication entitled Threshold Limit Values and Biological Exposure Indices, dated 1994-1995, as amended from time to time;

• (b) airborne grain dust in excess of 10 mg/m³; or

• (c) airborne chrysotile asbestos in excess of one fibre per cubic centimetre.

(2) Subsection (1) does not apply in respect of concentrations of carbon dioxide or respirable dust in the underground portion of a coal mine.

(3) Where there is a likelihood that the concentration of an airborne chemical agent may exceed the value referred to in subsection (1), air samples shall be taken and the concentration of the chemical agent shall be determined

• (a) in accordance with the standards set out by the American Conference of Governmental Industrial Hygienists in its publication entitled Manual of Analytical Methods Recommended for Sampling and Analysis of Atmospheric Contaminants, dated 1958, as amended from time to time;

• (b) in accordance with the standards set out by the United States National Institute for Occupational Safety and Health in the NIOSH Manual of Analytical Methods, third edition, volumes 1 and 2, dated February, 1984, as amended from time to time;

• (c) in accordance with a method that collects and analyses a representative sample of the chemical agent with accuracy and with detection levels at least equal to those which would be obtained if the standards referred to in paragraph (a) or (b) were used; or

• (d) where no specific standards for the chemical agent are set out in the publications referred to in paragraphs (a) and (b) and no method is available under paragraph (c), in accordance with a scientifically proven method used to collect and analyse a representative sample of the chemical agent.

(4) A written or computerized record of each test made pursuant to subsection (3) shall be kept by the employer at the employer’s place of business nearest to the work place where the air sample was taken, for a period of three years after the date of the test.

(5) A record referred to in subsection (4) shall include

• (a) the date, time and location of the test;

• (b) the hazardous substance in respect of which the test was made;

• (c) the sampling and testing method used;

• (d) the result obtained; and

• (e) the name and occupation of the person who made the test.