June 27, 2009

This environment could be considered a confined space in some jurisdictions.

Some would classify this work environment as a confined space

Do the above photos show examples of confined spaces? The answer can change depending on who is asked and where it is.

Ongoing Education

Definition of confined spaces needs makeover: expert

Mention the term confined space on a job site and everyone will have some idea of what you’re talking about.

The problem is, they won’t necessarily agree on what it means from province to province and across jurisdictions.

“The term dates well back into the last century,” said Neil McManus, president of NorthWest Occupational Health & Safety in Vancouver.

“It became synonymous with spaces that became workspaces following the opening of normally sealed equipment and structures, or workspaces that were entered infrequently.

“Today, depending on where you are, the term is exclusively geometry-based, while some jurisdictions include atmospheric hazards and still others include safety hazards as well.”

McManus wrote the book on confined spaces—literally.

His volume, Safety and Health in Confined Spaces, is one of only two books written on the subject.

In the book, he argues that workplaces across Canada need to take a simplified approach to safety in confined spaces that should be easily understood by both workers and management.

“Canadian regulators have a responsibility to the people being regulated to protect them in an effective manner,” he said.

“They can’t be protected effectively if they need a lawyer beside them to help interpret the regulations.

“We need to empower workers to do the right things for the right reasons. In many cases, the absolute proof that something is a confined space is in hindsight, when someone has been injured or killed in that space. In Ontario, if you die, it was definitely a confined space. If you don’t die, it might have been.”

In his safety training presentations, McManus typically offers his audience a series of workplace snapshots that they might encounter and asks them the simple question,

“Is this a confined space?”

The varying opinions of audience members make it clear that there’s no correct answer that will apply across Canada.

In one example, McManus shows photos of a building supported by pony walls that form a series of parallel channels.

To rehabilitate the site, contractors attempted to move contaminated soil from underneath the building using vacuum trucks.

When that idea proved unsuccessful, the contractor moved to Plan B, driving Bobcats down the tunnels to excavate the soil.

“When I analyzed the job, I could see that the vehicle would move in quickly, but back out slowly, right through the vehicle’s own exhaust gas,” he said.

“The circumstances of the job required us to treat those channels as a confined space.”

McManus remedied the situation by fashioning a ventilation system that would move air through the channels faster than the Bobcat could back up, ensuring that the operator had enough air to work safely.

An alarm system ensured that air of adequate quality reached the driver.

Other situations that often escape notice include sites where a large space becomes a confined space because it is half-filled with water.

A pre-cast concrete electrical vault may not be considered a confined space while sitting on a flatbed truck, but becomes a potential confined space hazard when lowered into an excavation.

An open-roofed structure can become a confined space in the presence of toxic heavier-than-air gases.

Even simple construction trenches are often overlooked as confined spaces because they’re covered under regulations that focus on other issues, he said.

McManus recounted an Ontario job in which construction workers entered large sewer pipes with heat guns to seal interior plastic liners at the joints.

“Whether that was a confined space became a hell of a big question,” he said.

McManus said that BC regulations have gone a long way to simplify the issues of what determines a confined space hazard.

Not so for Ontario.

“Ontario revamped its confined space regulations in 2005, but it’s disappointing to see what they ended up with,” he said.

“We can’t expend effort on classifying workspaces into pigeonholes according to arbitrary definitions. The real question the regulations need to answer is, ‘what hazardous conditions does this workspace pose and what must we do to eliminate, or at least control, them?’ Workers want a clear set of instructions to follow.”

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