Protecting workers from the physical hazards of confined spaces
A worker in B.C. was about to enter a confined space at night. The limited oxygen in this confined space might have been a respiratory hazard if not for the ventilation system that had been installed. Unfortunately, the solution created an additional hazard that he couldn’t see: the guard on the fan was broken. When the worker entered the space, he put his hand on the fan for support and instantly lost a few of his fingers.
“Dark, spooky, nasty, awful,” is how Lynanne Fortin describes confined spaces. She is the senior safety consultant for Ronin Safety & Rescue in Delta, B.C., who was on-site after the incident.
WorkSafeBC’s definition of a confined space is similar to that of other Canadian jurisdictions: “…an area that is enclosed or partially enclosed; is not designed or intended for continuous human occupancy; has limited or restricted means for entry or exit that may complicate the provision of first aid, evacuation, rescue or other emergency response service; and is large enough and so configured that a worker could enter to perform assigned work.”
Though confined spaces are not designed for humans, work often takes us there.
“People could be in there to do cleaning, welding, replacing, fixing something, removing or inspecting equipment, and sometimes for an entire shift,” says Jeremy Slater, regional sales manager for British Columbia at Acklands-Grainger in Vancouver.
Even when the work is routine, Slater says, the person entering the confined space must assess the hazards beforehand.
“Having a proper work plan for your confined space that highlights all the previous conditions and hazards is extremely important. And you should do a hazard assessment prior to entry every time because conditions can change from morning to afternoon,” he says.
Atmospheric hazards of confined spaces are well known, and safety crews today understand the need for appropriate gas monitors and respiratory protection. Yet there are other, “physical” hazards in confined spaces. Here are just a few:
Slippery surfaces: While a common control measure for slippery surfaces is to rinse down the space and let it dry, that may not work in certain confined spaces, such as a sewer system.
“I review the slippery surface with the worker during the pre-entry safety briefing. I am most concerned about the worker slipping and injuring his or her head, so the minimum PPE will include a helmet with a strong chin strap so it doesn’t go flying off,” says Scott Connor, president of TEAM-1 Academy in Oakville, Ont.
Falls from heights: Some confined spaces involve perilous heights. “The risk of falling is huge,” Fortin says. She describes incidents of people descending a manhole — using rungs in the cement wall — and the rotten cement giving way. Workers are also at risk of falling into pits or through openings in the floor.
Fall protection has a dual purpose. Not only does it protect a worker in the event of a fall, but the harness is something a rescuer can grab onto to pull a worker out.
Loose and unstable materials: Whenever unstable solids made of small particles like ?sand or grain are stored in enclosures, such as grain silos, there is a danger of the materials flowing onto workers and trapping or burying them.
Falling objects: A worker may be at risk of being struck by falling objects such as tools or equipment, particularly if access ports or work stations are located in an upper level. One way to avoid this is to schedule work activity so that no worker is working above another.
Mechanical equipment: Augers, mixers or rotating tanks can be dangerous if activated or not secured. Residual energy, such as gravity or accumulated pressure, also poses a risk unless the equipment is locked out and de-energized.
Poor visibility: A confined space with poor visibility not only increases the risk of injury but also makes it harder for another person to see a worker who may be in distress.
Also inherent in some confined spaces are temperature extremes, noise, electrical hazards, and even the risk of drowning.
Hazard assessments should be a priority for all health and safety professionals dealing with confined spaces. The time to identify all hazards is before anyone enters the confined space — not when something goes wrong. A hazard assessment must cover atmospheric hazards as well as any physical hazards.
“At a fixed facility (i.e. manufacturing plant) you can have hazard assessments prepared ahead of time so they can be used as reference,” Connor says. “But don’t forget to conduct another assessment based on the type of work that is actually going to be conducted.”
Prepare for rescue
When conducting a hazard assessment, consider the rescue — don’t imagine things always going smoothly. Imagine a worker breaking his leg in there and what must happen next. Practice the rescue and know how to call for help. Calling 911 isn’t necessarily ideal. While fire departments do respond, they have become less likely to provide a confined space extraction team. Instead, get to know an expert confined space rescue team or have an expert train your own internal team. A lifeline must also always be available.
“If something goes wrong you want the worker to self-rescue, if possible, so you won’t have to send someone else in — 80 per cent of fatalities in confined spaces are of the rescuers,” Fortin says.
Workers can self-rescue by pulling themselves out on the lifeline, up a reservoir, for example, or to avoid getting washed away in case of flooding in a sewer.
But make sure workers know how to properly set up the lifeline because it can entangle a worker if not properly set up.
OHS professionals should ensure communication systems are in place, as a fellow worker is another life-saving necessity. Ensure a reliable communication method between workers in the confined space and an “attendant” outside of it. This may include two-way radios, man down alarms or video. Simply yelling for help, while sometimes effective, is problematic in a large space where voices echo.
Equipment and PPE
Proper PPE should be used, as identified by the hazard assessment, and it should be regularly inspected and maintained.
“Make sure you have a plan in place, that your people are well trained, and that you have a good relationship with your safety specialist to supply equipment for your changing needs,” Slater says.
It’s also important to have the best safety equipment. It must be effective as well as easy to use, because sometimes workers don’t bother to set up safety equipment if they’re just going in for a quick or routine task; and adaptable, because confined spaces vary in so many ways.
One example of adaptable equipment is a davit, a mechanical arm with a winch for raising and lowering an object.
“While tripods are great if you’re in a manhole, as soon as that manhole is on a bit of a slope or on uneven ground it might not fit,” Slater says. Also, davits are much easier to use. “You just stick the pole into the socket and away you go.”
Appropriate lighting must be selected for confined spaces. A hot work space, for example, is the wrong place to use lights that produce additional heat. Also, the lighting shouldn’t be in the way. Connor’s rescue teams use head lamps, which keep both hands free.
“If you are doing work with any flammable vapours or gases present, you will want to make sure the lighting cannot cause any ignition, so you are going to need it to be intrinsically safe and/or explosion-proof rated,” Connor says.
Michelle Morra-Carlisle is a Toronto-based freelance writer. She can be reached at firstname.lastname@example.org.
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