Hot Work

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Hot work is defined in the legislation as “work that produces arcs, sparks, flames, heat or other sources of ignition”. This includes welding, soldering and cutting a wide variety of materials. Fires or explosions can result from quick, impromptu hot work jobs in areas not intended for that work. To prevent explosions and reduce the risk of fires breaking out, do not allow hot work in explosive atmospheres. Depending on the situation, you may be able to clear the air of combustible vapours or dust before beginning any hot work. Continuous monitoring of the hot work area for accumulation of combustible gases before, during, and after hot work is essential.

An employer or contractor shall:

  • Develop written procedures to ensure the health and safety of workers who perform hot work where there are or are intended to be flammable substances that pose a fire hazard.
  • Not start hot work until the written procedures have been implemented so that there is ongoing attention to safety during the hot work.
  • Make sure no hot work begins before the surrounding atmosphere is tested if flammable substances are or may be present.
  • Atmospheric testing must show:
    • whether the surrounding air has flammable substances in amounts that could be ignite and explode during the proposed hot work.
    • if it is safe for the planned hot work to be done in that area.
  • Make sure that area remains safe for ongoing hot work by repeating the tests as appropriate intervals. Take in account the specific type of hot work being performed when deciding when and how often to test.
  • Record all test results.
  • Not allow hot work near flammable or explosive materials as this is a fire hazard. Take suitable steps to reduce the risk of fire before hot work may begin.
  • Use an effective method to remove flammable substances from containers or piping before beginning any hot work on that container or piping.
  • Not allow welding or cutting of metal that has been cleaned with a flammable or combustible liquid until the metal has thoroughly dried.
  • Ensure that the gas burning or welding equipment has approved flashback devices on both hoses at the regulator end and acetylene and liquefied gas containers are used and stored in an upright position.
  • Make sure, all acetylene and liquefied gas containers are used and stored in an upright position.

Workers shall:

  • Shut off the container valve and release the pressure in the hose when the worker has finished with any gas burning or welding equipment and not likely to use it within the next two hours.
  • Use their provided personal protective equipment.
  • Take reasonable steps to prevent damage to provided personal protective equipment.

Personal Protective Equipment for Hot Work

Employers or contractors shall:

  • Provide and require for workers to wear any provided industrial eye or face protectors during hot work if they are at risk of irritation or injury, of their eyes or faces, from flying objects or particles, splashing liquids, molten metal or ultraviolet, visible or infrared radiation.
  • Take all reasonable steps to make sure electric arc welding is not performed if it could expose other workers to radiation unless they are wearing appropriate industrial eye protection or protected by an appropriate screen.
  • Provide, and require workers to use, approved protective clothing or covers or another safeguard with equal protection if there is a risk of injury to the skin of a worker from sparks, molten metal or radiation.
  • Provide workers require workers to wear fire resistant outer clothing if they are at risk of skin injuries from fire or explosion. Fire resistant clothing must meet the approved industry standard and be appropriate to the risk.
  • Require electrical workers to use arc flash protection that meets an approved standard if is a risk of skin injuries from arc flash.

Hot Work in Mines

An employer or contractor shall:

  • Designate areas where hot work is done as fire hazard areas and post and maintain legible fire hazard warning signs in visible and obvious locations around the boundary of the area.
  • Make sure every hot work area at underground mines have appropriate portable fire extinguishers and other fire-fighting equipment suited to the needs and hazards of that area.
  • Make sure, all acetylene and liquefied gas containers are used and stored in an upright position.
  • Make sure all compressed gas cylinders are stored in a safe place and are suitably and adequately secured.
  • Make sure cylinders of compressed gas being transported underground are protected from damage.
  • Disconnect all fittings, including regulators and manifolds from the compressed gas cylinders being transported underground except if the cylinders are secured in an upright position and the fittings are protected by a suitable safety cage or safeguard.
  • Only use cylinders of compressed gas to fuel hot work equipment underground. No other device or equipment that produces gas is permissible.
  • If reasonably practical before beginning hot work outside a designated shop or garage, use water to thoroughly wet down all combustible material, within a three-metre radius of the hot work. Repeat this wet down after the hot work is finished. Complete a fire watch by regularly checking the area for two hours after completing the hot work.
  • Make adequate fire-fighting equipment readily available at all times while the hot work is being done and during the fire watch.
  • Not allow hot work within eight metres of any place storing or transporting explosives.
  • Appropriately ventilate areas where hot work takes place.
  • Make sure another competent worker is always present and ready to operate the cylinder control devices, when a cylinder of compressed gas is operated from a location underground or in a conveyance that is not readily accessible hot work equipment operator. Make sure there is an effective and working means of communication between the worker operating the hot work equipment and the worker operating the cylinder control device.
  • If a cylinder of compressed gas is used to supply hot work equipment, ensure that the cylinder is located, guarded and handled during use so that the cylinder and its fittings are protected from damage.

Occupational Health and Safety Regulations, 1996
S.S., c. O-1.1, Reg 1

Part XXV Fire and Explosion Hazards

Section 359 Interpretation

359. In this Part:

(a) "combustible liquid" means a liquid that has a flashpoint at or above 37.8 Celsius and below 93.3 Celsius;

(b) "container" means a stationary or portable vessel that is used to contain a flammable substance, and includes a tank, tank car, tank truck and a cylinder;

(c) "flammable liquid" means a liquid that has a flashpoint below 37.8 Celsius and has a vapour pressure not exceeding 275.8 kilopascals at 37.8 Celsius;

(d) "flammable substance" means:

(i) a flammable or combustible solid, liquid or gas; or

(ii) dust that is capable of creating an explosive atmosphere when suspended in air in concentrations within the explosive limit of the dust;

(e) "hot work" means work that produces arcs, sparks, flames, heat or other sources of ignition;

(f) "system" means a system into which compressed or liquified gases are delivered and stored and from which the compressed or liquified gas is discharged in the liquid or gaseous form, and includes containers, pressure regulators, pressure relief devices, manifolds, interconnecting piping and controls.

Section 363 Procedures for flammable substances

363. (1) Where a flammable substance is or is intended to be handled, used, stored, produced or disposed of at a place of employment, an employer, contractor or owner shall develop written procedures to ensure the health and safety of workers who:

(a) handle, use, store, produce or dispose of a flammable substance that may spontaneously ignite or ignite when in combination with any other substance; or

(b) perform hot work where there is a risk of fire.

(2) An employer, contractor or owner shall ensure that all workers who are required or permitted to perform work mentioned in subsection (1) are trained in, and implement, the procedures developed pursuant to subsection (1).

(3) Workers who perform work mentioned in subsection (1) shall implement the procedures developed pursuant to subsection (1).

Section 370 Hot work

370. (1) Where a flammable substance is or may be present, an employer or contractor shall ensure that no hot work is performed until:

(a) suitable tests have been conducted that:

(i) indicate whether the atmosphere contains a flammable substance in a quantity sufficient to create an explosive atmosphere; and

(ii) confirm that the work may be safely performed; and

(b) the work procedures developed pursuant to clause 363(1)(b) have been implemented to ensure continuous safe performance of the work.

(2) While hot work is being performed, an employer or contractor shall conduct tests described in clause (1)(a) at intervals appropriate to the work being performed and record the results.

(3) An employer or contractor shall not require or permit any hot work to be performed in the vicinity of a material that may constitute a fire hazard until suitable steps have been taken to reduce the risk of fire.

(4) An employer or contractor shall ensure that a container or piping that contains or has contained a flammable substance is purged using an effective method to remove the flammable substance from the container or piping before any hot work is begun on that container or piping.

(5) An employer or contractor shall not require or permit any welding or cutting of metal that has been cleaned with a flammable or combustible liquid until the metal has thoroughly dried.

Section 373 Gas burning and welding equipment

373. (1) Where gas burning or welding equipment is in use, an employer or contractor shall ensure that:

(a) approved flashback devices are installed on both hoses at the regulator end; and

(b) acetylene and liquified gas containers are used and stored in an upright position.

(2) A worker shall shut off the container valve and release the pressure in the hose when the worker has finished with any gas burning or welding equipment and is not likely to use it within the next two hours.

Part VII Personal Protective Equipment

Section 87 General responsibilities

87. (1) Where an employer or contractor is required by these regulations or any other regulations made pursuant to the Act to provide personal protective equipment, the employer or contractor shall:

(a) supply approved personal protective equipment to the workers at no cost to the workers;

(b) ensure that the personal protective equipment is used by the workers;

(c) ensure that the personal protective equipment is at the worksite before work begins;

(d) ensure that the personal protective equipment is stored in a clean, secure location that is readily accessible to workers;

(e) ensure that each worker is aware of the location of the personal protective equipment and trained in its use;

(f) inform the workers of the reasons why the personal protective equipment is required to be used and of the limitations of its protection; and

(g) ensure that personal protective equipment provided to a worker:

(i) is suitable and adequate and a proper fit for that worker;

(ii) is maintained and kept in a sanitary condition; and

(iii) is removed from use or service when damaged.

(2) Where an employer or contractor requires a worker to clean and maintain personal protective equipment, the employer shall ensure that the worker has adequate time during normal working hours without loss of pay or other benefits for this purpose.

(3) Where reasonably practicable, an employer or contractor shall make appropriate adjustments to the work procedures and the rate of work to eliminate or reduce the danger or discomfort to the worker that may arise from the worker's use of personal protective equipment.

(4) A worker who is provided with personal protective equipment by an employer or contractor shall:

(a) use the personal protective equipment; and

(b) take reasonable steps to prevent damage to the personal protective equipment.

(5) Where personal protective equipment provided to a worker becomes defective or otherwise fails to provide the protection it was intended for, the worker shall:

(a) return the personal protective equipment to the employer or contractor; and

(b) inform the employer or contractor of the defect or other reason why the personal protective equipment does not provide the protection that it was intended to provide.

(6) An employer or contractor shall immediately repair or replace any personal protective equipment returned to the employer or contractor pursuant to clause (5)(a).

Section 93 Eye and face protectors

93. (1) Where there is a risk of irritation or injury to the face or eyes of a worker from flying objects or particles, splashing liquids, molten metal or ultraviolet, visible or infrared radiation, an employer or contractor shall provide industrial eye or face protectors and require the worker to use them.

(2) Where an industrial eye or face protector is required by these regulations to be provided or used, the industrial eye or face protector must be approved.

(3) An employer or contractor shall take all reasonable steps to ensure that a worker does not perform electric are welding if another worker may be exposed to radiation from the are unless the other worker is using a suitable industrial eye protector or is protected from the radiation by a suitable screen.

(4) A worker shall not perform electric are welding if another worker may be exposed to radiation from the are unless the other worker is using a suitable industrial eye protector or is protected from the radiation by a suitable screen.

Section 94 Skin protection

94. (1) Where there is a risk of injury to the skin of a worker from sparks, molten metal or radiation, an employer or contractor shall provide, and require the worker to use, approved protective clothing or covers or any other safeguard that provides equivalent protection for the worker.

(2) Where there is a risk of injury to the skin of a worker from fire or explosion, an employer or contractor shall provide the worker with, and require the worker to use, outer fire resistant clothing that:

(a) meets an approved industry standard; and

(b) is appropriate to the risk.

(3) Where there is a risk of injury to the skin of an electrical worker from arc flash, an employer or contractor shall provide the electrical worker with, and require the electrical worker to use, arc flash protection that meets an approved standard.

[Sask. Reg. 67/2007, s. 5]

Mines Regulations, 2003
R.R.S., c. O-1, r. 2

Part XVII Fire Prevention and Control

Section 352 Fire hazard area

352. (1) If a risk of fire exists in any area of a mine as a result of smoking or the use of any open flame equipment, match or other means of producing heat or fire, an employer or contractor must designate the area as a fire hazard area.

(2) If an area has been designated as a fire hazard area pursuant to subsection (1), an employer or contractor must ensure that legible fire hazard warning signs are posted and maintained in conspicuous locations around the perimeter of the area.

Section 355 Fire-fighting equipment

355. (1) An employer or contractor must ensure that there are suitable and adequate portable fire extinguishers and other suitable and adequate fire-fighting equipment:

(a) in the case of an open pit mine:

(i) on each vehicle;

(ii) on every dredge;

(iii) at every belt conveyor drive unit; and

(iv) at any location where a fire may create a hazard to a worker; and

(b) in the case of an underground mine:

(i) at each headframe or other entrance to an underground mine;

(ii) in each hoist room;

(iii) at any surface location where a fire may create a hazard to a worker;

(iv) on each vehicle and at each stationary diesel engine;

(v) at every underground crusher station, electrical installation, pump station, shaft station, belt conveyor drive unit, service garage, fuel station, explosive storage area, flammable liquid storage area and hot work area; and

(vi) at any other area that is designated as a fire hazard area pursuant to section 352.

(2) An employer or contractor must ensure that the fire-fighting equipment required pursuant to subsection (1) is:

(a) conspicuously marked; and

(b) located so that, in the event of a fire, it will be accessible.

Section 370 Hot work and use of compressed gas

370. (1) In this section, "hot work equipment" means equipment that produces arcs, sparks, flames, heat or other sources of ignition, and includes welding equipment, cutting equipment and brazing equipment.

(2) An employer or contractor must ensure that:

(a) all acetylene and liquified gas containers are used and stored in an upright position; and

(b) all compressed gas cylinders are stored in a safe place and are suitably and adequately secured.

(3) If cylinders of compressed gas are being transported underground, an employer or contractor must ensure that:

(a) the cylinder valves are protected from damage; and

(b) all fittings, including regulators and manifolds, are disconnected from the cylinders, unless:

(i) the cylinders are secured in an upright position; and

(ii) the fittings are protected by a suitable and adequate cage or safeguard.

(4) An employer or contractor must ensure that no device or equipment that produces gas, other than a cylinder of compressed gas, is used to fuel hot work equipment underground.

(5) Subject to subsection 363(1) of the OHS regulations, if hot work is performed an employer or contractor must ensure that:

(a) outside a designated shop or garage:

(i) if reasonably practicable, all combustible material within a three-metre radius of the hot work or on which sparks or hot material may fall is thoroughly wetted with water before the hot work begins and after it is finished; and

(ii) the area is regularly checked for two hours after the completion of the hot work;

(b) adequate fire-fighting equipment is readily available at all times while the hot work is being done and during the fire watch mentioned in clause (a);

(c) hot work is not conducted within eight metres of any place where explosives are being stored or transported; and

(d) any area in which hot work takes place is suitably and adequately ventilated.

(6) If a cylinder of compressed gas is operated from a location underground or in a conveyance that is not readily accessible to the worker who is operating the hot work equipment, an employer or contractor must ensure that:

(a) another competent worker is present at all times and ready to operate the cylinder control devices; and

(b) there is a suitable and adequate means of communication between the worker operating the hot work equipment and the worker operating the cylinder control device.

(7) If a cylinder of compressed gas is used to supply hot work equipment, an employer or contractor must ensure that the cylinder is located, guarded and handled during use so that the cylinder and its fittings are protected from damage.