The 2009 Alberta OH&S Code includes definitions of “restricted areas”, “restricted spaces” and “confined spaces”. Although their wording is similar, these three concepts are distinct, and knowing the different definitions of each can greatly aid understanding of the legislation.
A restricted space is an enclosed or partially enclosed space in which work is performed, not designed or intended for continuous human occupancy, that has restricted, limited or impeded means of entry or exit because it it’s construction. This definition of restricted spaces is exceedingly broad: Anything from crawl spaces to attics to cisterns to a child’s treehouse can meet the definition (though, admittedly, very little industrial or construction work is performed in a child’s treehouse). Restricted spaces are addressed in Part 5 of the Alberta OH&S Act, “Confined Spaces”, which details the following requirements: employers must perform a hazard assessment in addition to the requireded Part 2 assessment, any required safety or personal protective equipment (as well as a communication system) must be available and used, unauthorized persons must be prevented from entering the space, workers must be protected from hazards created by traffic in the area of the restricted space, workers cannot remain in the space unless an effective rescue can be executed, a competent worker must be in communication with the workers inside the space, and a safe means of entry and exit must be available to all workers in the restricted space.
A restricted space should not be confused with a “restricted area”, an area of a worksite where the airborne concentration of a dangerous dust such as coal dust or silica exceeds or may exceed the occupational exposure limit. Restricted areas are dealt with in Section 29 of the Alberta OH&S Act, under “Part 4: Chemical Hazards, Biological Hazards, and Harmful Substances”.
A confined space is defined as a restricted space which “may become hazardous to a worker entering it”. Thus, confined spaces are a specific type of restricted space, one in which the potential hazards within the space pose dangers above and beyond the mere difficulty of entering or leaving the space. These hazards can emerge from atmosphere, circumstance or activity. Atmospheric hazards can be due to an absence or overabundance of oxygen, flammable or explosive gases or particles or toxic substances in the atmosphere. Circumstantial hazards cover a wide variety of actual and potential threats posed by the nature or contents of a space. A good example would be massed particulate matter which can suddenly shift and engulf a worker in the confined space. Finally, activity-related hazards are those which result from an activity performed within the space, such as welding or the use of chemical cleaners. Confined spaces are, logically enough, addressed at length in “Part 5: Confined Spaces” of the Alberta OH&S Code, and subject to more stringent regulation than restricted spaces. In particular and in addition to the requirements for restricted spaces, employers are required to provide a code of practice governing how workers enter and work in a confined space, an entry permit system controlling entry, atmospheric monitoring if required, and a tending worker (one trained in emergency evacuation procedures) near the entrance of the confined space, again if required.
Thus, a restricted space which is also a restricted area would be considered a confined space, due to the presence of the hazardous atmosphere which defines a restricted area. It’s that simple!