Aviation Occupational Health and Safety Regulations — 5.1
 or disturbance of more than 1 m 2 of friable asbestos-containing material in a work place, even if the activity is divided into smaller jobs, (b) the spray application of a sealant to a friable asbestos-containing material, (c) the cleaning or removal of air-handling equipment, other than filters, in a building that has sprayed-on fireproofing or sprayed-on thermal insulation that is asbestos-containing material, (d) the repair, alteration or demolition of all or part of a kiln, metallurgical furnace or similar structure that contains asbestos-containing material, (e) the breaking, cutting, drilling, abrading, grinding, sanding or vibrating of non-friable asbestos-containing material, if the activity is carried out by means of power tools that are not attached to dust-collecting devices equipped with HEPA filters, and (f) the repair, alteration or demolition of all or part of a building in which asbestos is or was used in the manufacture of products, unless the asbestos was cleaned up and removed. ( activité à risque élevé ) lower explosive limit means the lower limit of flammability of a chemical agent or a combination of chemical agents at ambient temperature and pressure, expressed (a) for a gas or vapour, as a percentage in air by volume; and (b) for dust, as the weight of dust per volume of air. ( limite explosive inférieure ) low-risk activity means an activity that involves the handling of asbestos-containing material or is carried out in proximity to non-friable asbestos-containing material and that includes (a) the installation or removal of ceiling tiles that are made of non-friable asbestos-containing material and cover an area of less than 7.5 m 2 , (b) the installation or removal of other non-friable asbestos-containing material, if the material is not being broken, cut, drilled, abraded, ground, sanded or vibrated and dust is not being generated, (c) the breaking, cutting, drilling, abrading, grinding, sanding or vibrating of non-friable asbestos-containing material, if the material is wetted to control the spread of dust or fibres and the activity is carried out only by means of non-powered hand-held tools, and (d) the removal of less than 1 m² of drywall in which joint cement containing asbestos has been used. ( activité à faible risque ) moderate-risk activity means an activity that involves the handling of asbestos-containing material or is carried out in proximity to friable asbestos-containing material, that is not otherwise classified as a low-risk activity or high-risk activity and that includes (a) the removal of all or part of a false ceiling to gain access to a work area, if asbestos-containing material is likely to be found on the surface of the false ceiling, (b) the removal or disturbance of 1 m 2 or less of friable asbestos-containing material during repair, alteration, maintenance or demolition work in a work place, (c) the enclosure of friable asbestos-containing material, (d) the application of tape, sealant or other covering to pipe or boiler insulation that is asbestos-containing material, (e) the removal of ceiling tiles that are asbestos-containing material, if the tiles cover an area of greater than 2 m 2 and are removed without being broken, cut, drilled, abraded, ground, sanded or vibrated, (f) the breaking, cutting, drilling, abrading, grinding, sanding or vibrating of non-friable asbestos-containing material, if the material is not wetted to control the spread of dust or fibres and the activity is carried out only by means of non-powered hand-held tools, (g) the removal of 1 m 2 or more of drywall in which joint cement that is asbestos-containing material has been used, (h) the breaking, cutting, drilling, abrading, grinding, sanding or vibrating of non-friable asbestos-containing material, if the activity is carried out by means of power tools that are attached to dust-collecting devices equipped with HEPA filters, (i) the removal of insulation that is asbestos-containing material fro