The Occupational Health and Safety Act of Ontario, for instance, states that asbestos is classified as a designated substance in some workplaces. Hence employers are obliged to provide safety measures when they use a designated substance like asbestos.

The employer can only keep the amount of asbestos dust low, in order to reduce the possibilities of its workers of getting ill due to asbestos fibers inhalation or swallowing.

Designated Substances are hazardous substances that can be a biological, chemical or physical agent or combination thereof prescribed as a designated substance to which the exposure of a worker is prohibited, regulated, restricted, limited or controlled. Some regulations specify different procedures to control designated substances such as Acrylonitrile, Arsenic, Asbestos, Asbestos - Construction, Building and Repair, Benzene, Coke Oven Emissions, Ethylene Oxide, Isocyanates, Lead, Mercury, Silica and Vinyl Chloride among others.

The Occupational Health and Safety Act mentioned states that the employer has to review the work methods and assess the likelihood of worker exposure, when a designated substance such as asbestos is present in the workplace.

The control program, when there are risk of worker exposure to hazardous minerals like asbestos that can produce asbestosis or another asbestos-related diseases, must include engineering controls, work practices, hygiene practices, record keeping and medical surveillance.