Definitions

6.133   (1) In the combustible dust provisions:

"combustible dust" means a dust that is ignitable or deflagrable;

"combustible dust management program" means a program under section 6.141;

"combustible dust provisions" means sections 6.133 to 6.159;

"combustion hazard" means a factor that could give rise to a combustion that could cause injury or death to a person;

"combustion risk" means the likelihood that a combustion hazard could give rise to a combustion that could cause injury or death to a person;

"combustion risk assessment" means an assessment under section 6.140;

"competent ignition source", in relation to a combustible dust, means an ignition source that is sufficient to ignite the dust in one or both of the following circumstances:

(a) when the dust is suspended in air;

(b) when the dust is not suspended in air;

"conveying system" means a mechanized system that moves dust, or materials that include dust, from one location or operation on a worksite to another location or operation on the worksite, such as a conveyor belt system, bucket elevator system or pneumatic conveying system, but does not include

(a) a dust collection system,

(b) a vacuum cleaning system, or

(c) moving dust using mobile equipment;

"deflagration" means a flame that spreads rapidly outwards from the point of ignition through dust suspended in air;

"dust collection system" means a mechanized system or device used to capture and contain dust suspended in air;

"dust record" means any of the following:

(a) a determination under section 6.138 or 6.139;

(b) a combustion risk assessment;

(c) a combustible dust management program;

"enclosure" means a space, whether wholly or partially enclosed, in which air pressure could build;

"fire" includes smouldering but does not include deflagrations;

"handle", in relation to dust, means to use, store, transport or otherwise handle the dust;

"metal dust" means a dust more than 10% of which, by mass, is made of metal;

"minimize" means to eliminate or, if that is not practicable, to reduce to the lowest level practicable;

"minimum ignition energy (MIE)" means the lowest energy a competent ignition source needs to ignite a combustible dust suspended in air;

"mobile equipment" means the following machinery and equipment:

(a) a self-propelled ground machine with wheels or endless tracks or that is operated on rails or fixed tracks;

(b) any equipment attached to or towed by the machine;

"pneumatic conveying system" means a conveying system that moves a controlled flow of dust using air or other gases as the conveying medium;

"relevant machinery and equipment" means machinery or equipment that

(a) generates or handles combustible dust, or

(b) is part of a system that generates or handles combustible dust;

"vacuum cleaning system" means a mechanized system or device used to capture and contain dust that is on surfaces.

(2) For certainty, a reference to machinery or equipment in the following provisions is to be read to include an enclosure used for bulk storage of combustible dust:

(a) section 6.140 [combustion risk assessment];

(b) section 6.141 [combustible dust management program];

(c) section 6.147 [competent ignition sources];

(d) section 6.150 [foreign substance control];

(e) section 6.152 [capture of combustible dust];

(f) section 6.156 [relevant machinery and equipment].

What dust is covered

6.134   (1) Subject to subsection (2), the combustible dust provisions apply in relation to dust at a workplace if the dust is an input, product, byproduct or waste of a work process.

(2) The combustible dust provisions do not apply in relation to

(a) a workplace where there is no reasonably foreseeable risk of injury or death to a worker from the combustion of dust, or

(b) dust that is in a sealed commercial package.

General duty

6.135   An employer who generates or handles dust at a workplace must

(a) minimize the combustion risks, if any, for the dust, and

(b) without limiting paragraph (a),

(i) identify under section 6.137 whether the dust is a combustible dust,

(ii) if the dust is a combustible dust, prepare and update a combustion risk assessment under section 6.140 for the dust, and

(iii) if the combustion risk assessment identifies a combustion hazard in relation to the dust,

(A) prepare, implement and update a combustible dust management program under section 6.141 for the dust, and

(B) provide instruction and training under section 6.143 in relation to the combustion hazard.

Consultation

6.136   (1) An employer must consult in accordance with subsection (2) on

(a) preparation of a combustion risk assessment,

(b) preparation of a combustible dust management program,

(c) updates to a combustion risk assessment or a combustible dust management program that are required by section 6.135 (b), and

(d) instruction and training that is required by section 6.135 (b).

(2) A consultation on a matter under subsection (1) that relates to a workplace must be carried out with

(a) the joint committee for the workplace,

(b) the worker health and safety representative for the workplace, or

(c) if there is no joint committee or worker health and safety representative, a representative sample of the workers of the employer who are working at the workplace.

Identification of combustible dust

6.137   An employer who is required under section 6.135 (b) to identify whether a dust is a combustible dust must assume that

(a) the dust is ignitable unless the employer determines in accordance with section 6.138 that the dust is not ignitable, and

(b) the dust is deflagrable unless the employer determines in accordance with section 6.139 that the dust is not deflagrable.

Identification of combustible dust — ignitability

6.138   A determination for the purposes of section 6.137 (a) must be in writing and must be made in consultation with a qualified person and based on information derived using one or more of the following methods:

(a) by testing a representative sample based on

(i) the UN Recommendations on the Transport of Dangerous Goods, Manual of Tests and Criteria, Seventh edition, Part III, Section 33.2.4.3.1, Preliminary screening test, as amended from time to time, or

(ii) a similar screening test published by a national or international body or standards association;

(b) by considering objective data about the dust that is derived using a screening test referred to in paragraph (a) and published by a provincial, national or international body or standards association.

Identification of combustible dust — deflagrability

6.139   A determination for the purposes of section 6.137 (b) must be in writing and must be made in consultation with a qualified person and based on information derived using one or more of the following methods:

(a) by testing a representative sample based on

(i) the Go/No Go screening test methodology in the ASTM E1226-19, Standard Test Method for Explosibility of Dust Clouds, as amended from time to time,

(ii) the ASTM E1515-14, Standard Test Method for Minimum Explosible Concentration of Combustible Dusts, as amended from time to time, or

(iii) a similar screening test published by a national or international body or standards association;

(b) by considering objective data about the dust that is derived using a screening test referred to in paragraph (a) and published by a provincial, national or international body or standards association.

Combustion risk assessment

6.140   (1) A combustion risk assessment for a combustible dust must

(a) identify each combustion hazard for the dust, and

(b) set out the following information for each of those combustion hazards:

(i) the level of the combustion risk posed by the hazard;

(ii) any work processes or other factors that could increase the combustion risk posed by the hazard.

(2) A combustion risk assessment for a combustible dust must be

(a) in writing,

(b) prepared and updated in consultation with a qualified person, and

(c) based on the following factors:

(i) the physical characteristics, location and amount of the dust on surfaces, including, without limitation, whether the dust could escape a conveying system, vacuum cleaning system or dust collection system and fuel a deflagration;

(ii) the potential for dispersion and concentration of the dust in air, including, without limitation, whether a deflagration could spread between interconnected machinery or equipment;

(iii) the potential for confinement of the dust;

(iv) the presence of competent ignition sources;

(v) the presence of oxidants;

(vi) any other relevant factors.

(3) A combustion risk assessment must be updated as soon as practicable after there is a significant change in any of the following:

(a) rooms, buildings or other structures;

(b) machinery or equipment;

(c) work processes.

Combustible dust management program

6.141   (1) A combustible dust management program must

(a) describe how the employer will implement the controls required by sections 6.147 to 6.159, as applicable,

(b) specify any additional controls that are necessary to minimize combustion risks and describe how those controls are to be implemented,

(c) include schedules and procedures for carrying out regular inspections of any of the following that could give rise to a combustion risk:

(i) rooms, buildings or other structures;

(ii) machinery or equipment;

(iii) work processes,

(d) include procedures for responding to the failure of a control referred to in paragraph (a) or (b), and

(e) include procedures for responding to an unintended combustion of dust.

(2) A combustible dust management program must be

(a) in writing,

(b) prepared and updated in consultation with a qualified person, and

(c) based on the following for each of the combustible dusts addressed by the program:

(i) the combustion risk assessment for the dust;

(ii) an assessment of the effectiveness of any controls that have already been implemented.

(3) A combustible dust management program must be updated as soon as practicable after a review under section 6.142, if changes are necessary to minimize combustion risks.

(4) An employer who is required under section 6.135 (b) to prepare, implement and update a combustible dust management program for a workplace must assign overall responsibility for coordination of the program to an individual who

(a) is the employer or an employee of the employer, and

(b) is knowledgeable about all of the following that are applicable to the workplace:

(i) the controls described in the program;

(ii) the safe operation of the relevant machinery and equipment.

Combustible dust management program — periodic review

6.142   For the purposes of section 6.141 (3), an employer must ensure that

(a) a qualified person reviews the entire combustible dust management program at least annually and recommends any changes necessary to minimize combustion risks, and

(b) a qualified person reviews the relevant parts of the combustible dust management program and recommends any changes necessary to minimize combustion risks if

(i) a combustion risk assessment for a combustible dust is updated under section 6.140 (3), or

(ii) an event described in section 6.141 (1) (d) or (e) occurs.

Instruction and training

6.143   An employer who is required under section 6.135 (b) to provide instruction and training in relation to a combustion hazard must ensure that each worker of the employer who could be exposed to a combustion risk posed by the hazard receives instruction and training on

(a) the hazard,

(b) the factors that could increase the combustion risk, and

(c) the applicable parts of the combustible dust management program.

Records

6.144   An employer must

(a) retain a dust record for as long as the employer generates or handles the dust to which the record relates, and

(b) ensure that a dust record includes the following information:

(i) the date the record is prepared or updated;

(ii) the names of the qualified persons consulted;

(iii) in the case of a determination under section 6.138 or 6.139, a copy of the information on which the determination is based.

Availability of records

6.145   An employer must ensure that dust records that relate to a workplace are readily available to

(a) the workers of the employer who are working at the workplace, and

(b) the joint committee or the worker health and safety representative, if any, for the workplace.

Who must implement risk controls

6.146   Sections 6.147 to 6.159 apply to an employer in relation to dust at a workplace if the employer is required under section 6.135 (b) to prepare, implement and update a combustible dust management program for the dust at the workplace.

Competent ignition sources

6.147   (1) An employer must ensure that, in areas where a combustible dust is generated or handled, competent ignition sources are

(a) removed, or

(b) if removal is not practicable, controlled to minimize combustion risks.

(2) Without limiting subsection (1), an employer must ensure that

(a) all machinery and equipment directly exposed to a combustible dust is selected, located, installed, maintained and operated to minimize the risk of friction becoming a competent ignition source,

(b) a person does not engage in hot work or use machinery or equipment that gives off flames or sparks or handles hot material unless the person does so in accordance with work procedures, developed by the employer in consultation with a qualified person, that minimize combustion risks,

(c) the risk of the accumulation of electrostatic charge in machinery or equipment becoming a competent ignition source is minimized through grounding, bonding or other effective methods, and

(d) without limiting paragraphs (a) to (c), mobile equipment is selected, located, maintained and operated to minimize the risk of the mobile equipment becoming a competent ignition source.

(3) An employer must ensure that the machinery or equipment described in subsection (2) (c) is inspected and tested with sufficient frequency to ensure the effectiveness of the methods described in that subsection.

Oxidant control

6.148   If reduction of oxidant concentration is used to minimize combustion risks, an employer must ensure, in consultation with a qualified person, that oxidant concentrations are maintained within the range that will not support combustion.

Suspension control

6.149   An employer must ensure that the concentration of combustible dust suspended in air in the workplace does not become a combustion hazard.

Foreign substance control

6.150   If a foreign substance entering machinery or equipment could give rise to a combustion, by causing a reaction or otherwise, an employer must ensure that the risk of the foreign substance entering the machinery or equipment is minimized.

Bulk storage

6.151   (1) An employer who has a combustible dust in bulk storage, whether or not within an enclosure, must

(a) ensure that the combustion risks from heat-producing decomposition of the dust are minimized

(i) by controlling the factors, including moisture and stagnation, that could contribute to heat-producing decomposition of the dust, and

(ii) if the controls under subparagraph (i) are not adequate to minimize the risks, by also installing a self-heating detection mechanism, and

(b) prepare, in consultation with a qualified person, and ensure that workers of the employer comply with a written emergency response plan that sets out procedures and methods for

(i) responding to the combustion of the dust, and

(ii) determining whether the burning is extinguished.

(2) An employer who has a combustible dust in bulk storage within an enclosure must ensure that

(a) the enclosure is constructed or selected to have minimal elevated surfaces on which the dust can accumulate,

(b) the enclosure is filled and emptied

(i) in a way that minimizes the risk of electrostatic charge becoming a competent ignition source, and

(ii) if the enclosure has a roof or deflagration relief vents, so that persons are not on the roof or near the vents unless the employer ensures, in consultation with a qualified person, that being on the roof or near the vents, as the case may be, is safe, and

(c) without limiting section 6.157 [fire control], the workplace is equipped with a fire suppression system, or another means, that is adequate to suppress the burning of both the dust and, if combustible, the enclosure.

(3) An employer who has a combustible dust in bulk storage within an enclosure must consult with a qualified person and, if the bulk storage could give rise to a deflagration that could cause injury or death to a person, ensure that the enclosure

(a) is equipped with a deflagration suppression system, or

(b) has a design strength that exceeds the maximum reduced deflagration pressure, as determined by a qualified person, and is equipped to release deflagration pressure through deflagration relief vents that

(i) are located at the top of the enclosure or on the side of the enclosure above the maximum level of the stored dust,

(ii) are maintained in accordance with an applicable standard published by a national or international body or standards association, and

(iii) direct the pressure to

(A) a safe outdoor location, or

(B) a safe indoor location, if the vents are equipped with a flame-quenching device.

(4) An employer is not required to comply with subsection (2) (a) or (3) in relation to an enclosure, including, without limitation, a portable vacuum or an intermediate bulk container, if doing so is not practicable because of the size or portability of the enclosure.

Capture of combustible dust

6.152   (1) An employer must ensure that combustible dust escaping from machinery and equipment is

(a) minimized, and

(b) if the amount of dust escaping could give rise to a combustion, captured.

(2) If the dust is suspended in air, capture required under subsection (1) (b) must be carried out using a dust collection system, if practicable.

Removal of combustible dust

6.153   (1) This section does not apply in relation to metal dust.

(2) If combustible dust could accumulate on surfaces, an employer must determine, in consultation with a qualified person, and document

(a) the maximum amount of the dust that will be allowed to accumulate on the surfaces, based on the combustion risk assessment for the dust,

(b) a schedule for regularly removing the dust from the surfaces so that accumulation of the dust does not exceed the maximum amount referred to in paragraph (a), and

(c) methods of removing the dust from the surfaces under paragraph (b).

(3) If dust accumulates in excess of a maximum amount referred to in subsection (2) (a), an employer must

(a) remove the dust to below that amount as soon as practicable, and

(b) in the meantime, minimize the combustion risk posed by the accumulated dust.

(4) For the purposes of subsections (2) (c) and (3) (a) and (b), an employer must determine methods so as to minimize

(a) the exposure of combustible dusts to competent ignition sources, and

(b) the suspension of dust in air in concentrations that could give rise to a combustion risk.

(5) An employer must ensure that compressed air is not used to remove combustible dust other than in accordance with the following requirements:

(a) the compressed air system must be equipped with a mechanism for regulating air pressure and set at the lowest air pressure that is effective to blow down the dust;

(b) each competent ignition source must be removed from the area, shut down or otherwise eliminated before using the compressed air;

(c) any dust that has been blown down onto surfaces in the area must be removed, using a method determined in accordance with subsection (4), before competent ignition sources are used.

Removal of combustible dust — metal dust

6.154   (1) This section applies in relation to metal dust that is combustible dust.

(2) If metal dust could accumulate on surfaces, an employer must determine, in consultation with a qualified person, and document

(a) the maximum amount of the dust that will be allowed to accumulate on the surfaces based on

(i) the combustion risk assessment for the dust,

(ii) whether the dust could react with a metal oxide and produce heat,

(iii) whether the dust could react with a substance and produce a flammable gas, and

(iv) whether the dust, if it combusts, could become molten metal,

(b) a schedule for regularly removing the dust from the surfaces so that accumulation of the dust does not exceed the maximum amount referred to in paragraph (a), and

(c) methods of removing the dust from the surfaces under paragraph (b).

(3) If dust accumulates in excess of a maximum amount referred to in subsection (2) (a), an employer must

(a) remove the dust to below that amount as soon as practicable, and

(b) in the meantime, minimize the combustion risk posed by the accumulated dust.

(4) For the purposes of subsections (2) (c) and (3) (a) and (b), subject to subsection (5), an employer must ensure that metal dust is removed using the following methods in order of priority:

(a) using conductive, non-sparking scoops and brooms that have

(i) conductive, non-sparking handles, and

(ii) brushes with soft and natural fibre bristles;

(b) using a vacuum cleaning system for any remaining dust after using the method in paragraph (a);

(c) using compressed air for areas that are inaccessible by brooms and vacuum cleaning systems;

(d) using any method using water or another substance that will not

(i) create a combustible concentration of dust suspended in air, or

(ii) react and give rise to a hazardous combustion.

(5) An employer is not required to give priority to a method under subsection (4) if the employer determines, in consultation with a qualified person, that doing so would be more hazardous than using a method with lower priority.

(6) An employer must ensure that a vacuum cleaning system is not used to remove metal dust other than in accordance with the following requirements:

(a) if the vacuum cleaning system is a portable vacuum cleaner, the waste collection bin of the portable vacuum cleaner is emptied at the end of each shift;

(b) before and after using the vacuum cleaning system for a substance other than the dust, the system is thoroughly cleaned unless

(i) the employer has consulted with a qualified person, and

(ii) the dust and the other substance will not react and give rise to a hazardous combustion.

(7) An employer must ensure that compressed air is not used to remove metal dust other than in accordance with the following requirements:

(a) the compressed air system must be equipped with a mechanism for regulating air pressure and set at the lowest air pressure that is effective to blow down the dust;

(b) each competent ignition source must be removed from the area, shut down or otherwise eliminated before using the compressed air;

(c) any dust that has been blown down onto surfaces in the area must be removed, using a method determined in accordance with subsections (4) and (5), before competent ignition sources are used.

Other requirements in relation to metal dust

6.155   (1) This section applies in relation to metal dust that is combustible dust.

(2) An employer must ensure that workers of the employer who handle a metal dust with a minimum ignition energy (MIE) below 30 mJ

(a) are grounded through personal protective equipment, and

(b) use metal tools that are grounded, bonded and made of spark-resistant material.

(3) If metal dust is present in a work area, an employer must ensure that flammable substances in the work area are limited to the quantity reasonably needed for one work shift.

(4) If use of a pneumatic conveying system with an air-moving device to transport metal dust gives rise to a combustion hazard, an employer must, in consultation with a qualified person, regulate the manner and amount of worker access to and around the system in order to minimize the risk of injury or death to a person.

Relevant machinery and equipment

6.156   (1) An employer must ensure that relevant machinery and equipment is maintained and operated so as to minimize combustion risks.

(2) An employer must ensure that relevant machinery and equipment is selected, located and, if applicable, installed

(a) in consultation with a qualified person, and

(b) so as to minimize combustion risks.

(3) If relevant machinery and equipment is modified by or for an employer, the employer must also ensure that the machinery and equipment is modified

(a) in consultation with a qualified person, and

(b) so as to minimize combustion risks.

(4) If relevant machinery and equipment is designed by or for an employer, the employer must also ensure that the machinery and equipment is designed and constructed

(a) in consultation with a qualified person, and

(b) so as to minimize combustion risks.

Fire control

6.157   (1) An employer who has combustible dust at the workplace must be able to suppress a fire at the workplace using a means that is

(a) selected and installed in consultation with a qualified person, and

(b) adequate to minimize

(i) the combustion risks for the dust, and

(ii) the effects of a combustion of the dust or, if applicable, a substance produced by a reaction involving the dust.

(2) An employer must ensure that a fire suppression system or other means under subsection (1) is operated in a way that minimizes the concentration of dust suspended in air.

Deflagration control

6.158   An employer who has combustible dust at the workplace must

(a) be able to minimize the effects of a deflagration involving the dust at the workplace using a means that is selected and installed in consultation with a qualified person, and

(b) if deflagration relief vents are used under paragraph (a), ensure that

(i) the vents are designed and located, in consultation with a qualified person, to minimize risk to the health and safety of workers and other persons in the event of a deflagration, and

(ii) the vents and the blast areas for the vents are marked with signs that clearly identify the hazard.

After a fire or deflagration

6.159   (1) An employer who has combustible dust at the workplace must have written procedures for safely resuming operations after a fire or deflagration involving the dust.

(2) If a fire or deflagration involving combustible dust occurs in the workplace, the employer must, before resuming affected operations,

(a) ensure that the combustion is extinguished and the controls described in sections 6.157 and 6.158 are restored to readiness, and

(b) advise the affected workers that the employer has met the requirements in paragraph (a).