Cold weather drives more construction tasks indoors, but that doesn’t necessarily protect workers from all the hazards that increase this time of year. Exposure to carbon monoxide (CO), the top cause of poisoning deaths in the United States and Canada, goes up when temperatures drop and more of the workday is spent inside.

What Is a Confined or Enclosed Space?

A confined or enclosed space has limited or restricted means for entry and exit or is not designed for continuous occupancy.

Confined spaces include, but are not limited to, crawlspaces, ductwork, tanks, vessels, silos, storage bins, hoppers, vaults, pits, manholes, tunnels, equipment housings and pipelines.

In the U.S alone, carbon monoxide exposures kill an average of 430 people every year and send nearly 5,000 others to emergency rooms. (This is believed to be an underestimate of CO poisoning because many people are misdiagnosed.) Survivors can be left with permanent brain damage.

Carbon Monoxide

Carbon monoxide is a byproduct of burning gasoline, propane, wood, charcoal and other fuels. Under the right circumstances, it can build up very quickly in rooms, basements and crawlspaces, in semi-enclosed structures like garages and porches and in other types of enclosed and confined spaces. Because it is colorless, odorless and tasteless, people can breathe in CO and be unaware that they are being poisoned.

CO blocks the absorption of oxygen in the bloodstream, promptly starving the vital organs. In a matter of minutes this can cause:

  • Headache
  • Dizziness
  • Drowsiness
  • Nausea
  • Tightness across the chest
  • Loss of consciousness
  • Death

Construction laborers using power saws, generators and other fuel-burning tools and equipment when working in enclosed spaces are at increased risk for carbon monoxide poisoning. Cold weather is not a prerequisite for exposure to carbon monoxide, but it does increase the risk.

LIUNA General Secretary-Treasurer and LHSFNA Labor Co-Chairman Armand E. Sabitoni

“This is the time of year when indoor spaces are often sealed to keep out cooler temperatures and wind,” says LIUNA General Secretary-Treasurer and LHSFNA Labor Co-Chairman Armand E. Sabitoni. “While that is important for health and safety, it can reduce the amount of fresh air coming in. If precautions such as installing a ventilation system aren’t taken, carbon monoxide can build up and have deadly consequences.”

How can employers reduce the risk of carbon monoxide poisoning at jobsites?

  • Do not use gas-powered equipment in confined spaces.
  • Switch to equipment powered by electricity, batteries or compressed air if it can be used safely.
  • Educate employees about the sources and conditions that can lead to CO poisoning.
  • Install a ventilation system that will remove CO from work areas.
  • Install CO monitors with audible alarms.
  • Provide personal carbon monoxide monitors with audible alarms.
  • As required by OSHA, test air continuously in confined spaces and other areas where CO may be present.

What can employees do to reduce risk for carbon monoxide poisoning?

  • Be alert to ventilation problems and report them promptly to your supervisor.
  • Report feelings of dizziness, drowsiness or nausea immediately.
  • Don’t smoke. Smokers already have CO in their systems and are more easily poisoned by workplace exposures.
  • If you think you have CO poisoning, alert your supervisor and immediately leave the contaminated area.
  • Tell your doctor that you may have been exposed to CO if you get sick.

“Unless you are properly equipped and trained as an emergency rescuer, don’t enter an enclosed or confined space to rescue a coworker,” says Sabitoni. “More than 60 percent of confined space deaths are to would-be rescuers. Don’t put yourself in harm’s way. Call 911 and alert emergency personnel so first responders who are trained in CO rescue can be sent immediately.”

The LHSFNA has developed a new Confined Spaces page that summarizes OSHA’s new confined spaces rule and helps contractors understand its requirements, including the proper steps to take before, during and after entry into a confined space.

For more information about confined spaces, order the Fund’s Confined Spaces Health Alert or the Laborers’ Guide to Competent Persons through the online Publications Catalogue. The LHSFNA’s Occupational Safety and Health Division is also available at 202-628-5465 to further assist LIUNA signatory contractors with keeping their sites safe.

Stay Safe in Your Home

Malfunctioning and misused fuel-burning appliances can cause carbon monoxide to build up in your home. Take these steps and reduce this risk:

  • Schedule annual maintenance on furnaces, fireplaces, chimneys and other heat sources.
  • Install battery-operated carbon monoxide alarms in your home. (Check to see if your smoke detector also checks for carbon monoxide.) Check them twice a year to make sure batteries are working properly. A good time to do this is when clocks are adjusted for daylight saving time.
  • Operate portable generators outdoors and at least 25 feet from your house.
  • Never operate fuel-powered equipment or tools in a garage, basement or any enclosed space.
  • Never use a gas range or oven for warmth.
  • Never use a gas or charcoal barbecue grill in your home or other enclosed space.
  • Never run a car or truck inside your garage, even with the door open.
  • If you suspect that you or someone else has carbon monoxide poisoning, get out of your house immediately and call 911.

[Janet Lubman Rathner]