PART VI OCCUPATIONAL HEALTH REQUIREMENTS — Silica regulation

"blasting" means the cleaning, smoothing, roughening or removing of part of the surface of an article by the use as an abrasive of a jet of sand, metal shot or grit or other material propelled by compressed air or steam or by a wheel; sandblasting; total or partial enclosure of the process; enclosure apparatus and exhaust ventilation equipment used or likely to be used to contain silica dust is maintained and is inspected at least once in every 7 days and is certified by a competent person at least once in every calendar year; and approved respiratory protective equipment; and sandblasting is not done outside a blasting enclosure to an article which it is practicable to introduce into a blasting enclosure; constructed, operated and maintained to prevent the escape of dust; is not manufactured except under standards prescribed by the division;

"blasting chamber" means a blasting enclosure into which workers enter; the cleaning of castings; efficient local exhaust ventilation; effective means is provided to collect silica dust removed by exhaust ventilation equipment and to prevent its re-entry into a workroom, and every filtering or settling device situated in a workroom is completely separated from the general air of that workroom in an enclosure ventilated to the open air. protective clothing, including coveralls and headgear, that, when worn, exclude silica dust and that is maintained and cleaned in a safe manner. sand or other substance containing more than 1% by weight of respirable dust is not introduced into a blasting enclosure; provided with an efficient dust extraction system, which is kept in continuous operation whenever the blasting enclosure is in use whether or not blasting is actually taking place, and a blasting chamber is in operation when a worker is inside the chamber; is not used for a purpose for which a less hazardous substance may be substituted; and

"blasting enclosure" means a chamber, barrel, cabinet or other similar enclosure designed for the purpose of blasting in it; the blasting, fettling, grinding or dressing of a surface containing silica, including the engraving or abrasive cleaning of gravestones, buildings or structures of siliceous stones or rocks; jets or sprays of water or other suitable wetting agent; and sandblasting is not done except with the written permission of the officer and in accordance with the conditions and to the extent that the officer may prescribe; and specially inspected by a competent person once in every week in which it is used for blasting, and the enclosure, the apparatus connected with it and the ventilating plant associated with it is thoroughly examined and tested by a competent person once every month, and all results of required inspection, examinations and tests are recorded and all defects remedied without avoidable delay; and is not used in the manufacture of scouring powder or abrasive soaps or as an abrasive in a process.

"cleaning of castings" means, where done as an incidental or supplemental process in connection with the making of metal castings, the freeing of the castings from adherent sand or other substance, and includes the removal of cores and the general smoothing of the castings where the freeing is done, but does not include the freeing of castings from scale formed during annealing or heat treatment; a process in which silica flour is used; another method considered suitable by the assistant deputy minister. sandblasting is not done underground, and sandblasting shall not be undertaken nor performed by an employer, worker or self-employed person other than those registered for that purpose with the division. provided with efficient apparatus for separating where practicable the abrasive from other dust, and the abrasive is not again introduced into the blasting apparatus until it has been separated.

"sandblasting" means the process of projecting sand by means of compressed air or steam or by a wheel; the manufacture of silica-containing refractory bricks or silica-containing substances and the dismantling or repair of the refractory lining of furnaces;

"silica dust" means dust of respirable particle size and composed substantially of uncombined silica (Silicon Dioxide S i O 2 ); a process which the chief occupational medical officer has reason to believe creates a risk to the health of workers by silica dust; and

"silica flour" means the ground material produced by the milling of siliceous rocks or other siliceous substances, including diatomite (Kieselguhr, diatomaceous earth); a process that includes the getting, cutting, splitting, crushing, grinding, milling, drilling, sieving, or other mechanical manipulation of gravel or siliceous stone or rock where there is potential for exceeding 1% free silica or 50% of TLV.

"uncombined silica" means silica which is not combined chemically with another element or compound; and

"use of a parting material" means the application of a material to a surface of a pattern or of a mould to facilitate the separation of the pattern from a mould or the separation of parts of the mould.

The provisions of this section apply wherever workers are employed in a silica process, including

An employer shall ensure that at every silica process except sandblasting to which subsection (12) applies, the entry into the air of silica dust is prevented where reasonably practicable by the provision of

An employer shall ensure that

Where it is not reasonably practicable to prevent the entry into the air of silica dust, the employer shall provide for the isolation of the worker from the air containing silica dust.

Where it is not reasonably practicable to prevent the entry into the air of silica dust nor practicable to isolate the worker from the air containing silica dust, and for all cleaning and maintenance work, the employer shall provide for the use of each worker who may be exposed to silica dust

A worker shall not be required to perform work for which respiratory protective equipment and clothing is provided unless fully instructed in the need for and proper use of that equipment and clothing.

An employer shall ensure that all places where silica dust may accumulate are regularly cleaned using vacuum methods wherever practicable.

An employer shall ensure that the standard for dust levels does not exceed the threshold limit value (TLV) established by the ACGIH.

A worker who in the course of the worker’s employment is likely to be engaged in a silica process shall be warned by the employer of the danger to the worker’s health of inhaling silica dust and that the risk of injury is made greater by smoking.

Persons under the age of 18 shall not be employed in a silica process nor in cleaning or maintenance work likely to involve exposure to silica dust except work that is a recognized part of apprenticeship or comparable course of training.

An employer shall ensure that

An employer shall ensure where practicable that castings, gravestones and other articles which are liable to give rise to silica dust by blasting are not blasted except in a blasting enclosure, and that work is not performed in a blasting enclosure except blasting and work immediately incidental to that and the cleaning and repairing of the enclosure and of plant and appliances situated in that enclosure.

An employer shall ensure that every blasting enclosure which is liable to contain silica dust is

An employer shall provide and maintain for workers who work in a blasting chamber, whether in blasting or other work, protective blasters' helmets supplied with clean and not unreasonably cold air of not less than 6 cubic feet a minute, and the helmets shall be used by workers whenever they are in the blasting chamber.

Suitable gauntlets and coveralls shall be provided for the use of, and shall be worn by, all workers while performing blasting or assisting at blasting, and suitable provision shall be made for the storage, regular cleaning by vacuum and maintenance in good condition of the gauntlets and coveralls.

When a worker is engaged in the cleaning of a blasting apparatus or enclosure, ventilating or separating plant, or the surrounds, all practical measures shall be taken to prevent the inhalation of silica dust or its dissemination into the air and all the cleaning shall be by vacuum or hosing by water whenever practicable.

An employer shall ensure that silica flour

The examining physician shall record in the log the date and nature of the certificate the examining physician issues to each worker the examining physician has medically examined.