According to O. Reg 851 (179/07), a confined space is defined as “a fully or partially enclosed space that is not both designed and constructed for continuous human occupancy and in which atmospheric hazards may occur because of its construction, location or contents or because of the work that is done in it.” Examples of confined spaces include boilers, storage tanks, pits and sewers.

Hazards associated with confined spaces include oxygen deficiency, toxic vapours and combustible gases, solvents or dusts. In addition to atmospheric hazards, confined spaces often contain physical or mechanical hazards such as rotating machinery, electrical equipment or material which can engulf an entrant. The risks associated with all confined space hazards are further amplified by the typically tight quarters inside the space which make entry, exit and rescue difficult.

If an employer’s workplace includes a confined space that workers may enter to perform work, the employer must ensure that a written program for the confined space is developed and maintained in accordance with O. Reg 851 before any worker enters a confined space.

Confined Space Program Requirements

The major elements of a confined space program are as follows:

  • Assessment – A method for assessing the hazards to which workers may be exposed.
  • Recognition – A method for recognizing each confined space to which the program applies.
  • Entry Plan – A method for the development of one or more entry plans.
  • Training – A method for general training of workers
  • Permit System – An entry permit system that sets out the measures and procedures to be followed when work is to be performed in a confined space.