Prevent Carbon Monoxide Poisoning at Work

By Roy Maurer April 17, 2014

A recent mass casualty event in Fairfax County, Va., serves as a reminder for employers to take the necessary precautions to protect workers from the serious, and sometimes fatal, effects of carbon monoxide exposure.

A faulty furnace in a medical building led to 19 people being hospitalized March 24, 2014. Fairfax County Fire and Rescue Services reported high carbon monoxide levels in the building. The first responders were called after several people complained of nausea, which is common after carbon monoxide exposure.

What Is Carbon Monoxide?

Carbon monoxide (CO)—known as the “silent killer”—is a colorless, odorless and tasteless gas. The inability to easily detect it enhances its lethality. It is a common industrial hazard resulting from the incomplete burning of natural gas and any other material containing carbon such as gasoline, kerosene, oil, propane, coal or wood.

CO sources at home include gas- and oil-burning appliances such as furnaces, dryers, water heaters, ovens, wood-burning stoves, charcoal grills and automobiles.

In the workplace, CO exposure can occur in operations near furnaces, ovens, generators, forges and kilns. Some petroleum-product processes and gasoline-powered tools such as high-pressure washers, welders and pumps also produce CO, but one of the most common sources of occupational exposure is the internal combustion engine, according to the Occupational Safety and Health Administration (OSHA).

Workers in boiler rooms, breweries, docks, warehouses, petroleum refineries, pulp and paper production, steel production, and near blast furnaces or coke ovens are at risk of being exposed to harmful levels of carbon monoxide, OSHA said.

Carbon monoxide displaces oxygen in the blood and starves the heart, brain and other vital organs of oxygen. Large amounts of CO can suffocate an individual in minutes without warning.

Initial symptoms of CO poisoning may include tightness in the chest, headache, fatigue, dizziness, drowsiness or nausea. During prolonged or high exposures, symptoms may include vomiting, confusion and loss of consciousness.

CO poisoning can be reversed if caught in time, but acute poisoning could result in permanent heart and brain damage.

OSHA recommends the following prompt actions if you suspect CO poisoning:

  • Move the victim immediately to fresh air in an open area.
  • Call 911 or another local emergency number for medical assistance.
  • Administer 100-percent oxygen using a tight-fitting mask if the victim is breathing.
  • Administer cardiopulmonary resuscitation if the victim has stopped breathing.

OSHA warns employers that if the poisoning occurs in a confined space, rescuers could be exposed to fatal levels of CO. The agency advises rescue attempts in confined spaces only if rescuers are experienced at performing recovery operations and using recovery equipment.

Prevent Unsafe CO Exposure

The OSHA permissible exposure limit prohibits worker exposure to more than 50 parts per million parts of air averaged during an 8-hour time period. Exposure to concentrations over 100 parts per million constitutes a serious violation, and any exposure greater than 500 parts per million is considered imminent danger. The National Institute for Occupational Safety and Health (NIOSH), which conducts scientific research for OSHA, has recommended that the standard be changed to less than 40 parts per million and that any exposure beyond 200 parts per million be strictly prohibited.

To reduce the chances of CO poisoning in your workplace, OSHA recommends taking the following actions:

  • Install an effective ventilation system that will remove CO from work areas.
  • Maintain equipment and appliances (e.g., water heaters, space heaters, cooking ranges) to reduce CO formation.
  • Consider switching from gasoline-powered equipment to equipment powered by electricity, batteries or compressed air.
  • Prohibit the use of gasoline-powered engines or tools in poorly ventilated areas.
  • Install CO monitors with audible alarms. Provide personal CO monitors with audible alarms if potential exposure to CO exists.
  • Test air regularly in areas where CO may be present, especially in confined spaces.
  • Use a full-face pressure-demand self-contained breathing apparatus certified by NIOSH, or a combination full-face pressure-demand supplied-air respirator with auxiliary self-contained air supply in areas with high CO concentrations.
  • Use respirators with appropriate canisters for short periods under certain circumstances where CO levels are not exceedingly high.
  • Educate workers about the sources and conditions that may result in CO poisoning, as well as the symptoms and control of CO exposure.
  • Ensure that workers test for oxygen sufficiency before entering confined spaces.

Employees should be trained to do the following:

  • Report any situation to the employer that might cause CO to accumulate.
  • Be alert to ventilation problems—especially in enclosed areas where gases of burning fuels may be released.
  • Report complaints of dizziness, drowsiness or nausea promptly.
  • Avoid overexertion if CO exposure is suspected and leave the contaminated area.
  • Avoid the use of gas-powered engines, such as those in power washers, heaters and forklifts, while working in enclosed spaces.

Roy Maurer is an online editor/manager for SHRM.

Follow him @SHRMRoy



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