We were heading into a holiday so the loading dock was busier than usual. We had double the forklifts going through. A few hours into the shift, one of the workers started feeling lightheaded. Water didn't help, and it kept getting worse. It took us a while to realize that all those extra trucks going through meant he had been exposed to high levels of carbon monoxide.

While it’s not a common topic of discussion, carbon monoxide is very real threat to employees working in and around loading docks. CO is a colorless and odorless gas, which makes it nearly impossible to detect without a gas monitor. That makes understanding and managing the hazards paramount to ensuring a safe work environment.

How Does Exposure Happen?

Carbon monoxide is emitted from fuel-powered trucks that frequent the loading dock, such as forklifts. The concentration of gas in the dock area depends on a number of different factors, including:

  • Number of vehicles in operation
  • Size and efficiency of their engines
  • Length of time they spend idling
  • Driver technique
  • Size and shape of the building
  • Natural ventilation (building open or closed)
  • Mechanical ventilation (like power exhaust fans)

Most loading docks are enclosed, and without sufficient ventilation it’s easy for carbon monoxide emissions to build up quickly and endanger the health – and, in fact, the lives – of workers in the area.

What Employees Should Know

It’s essential that workers take responsibility for their health and well being. With respect to CO exposure, this means being educated about the potential hazards and understanding how to identify carbon monoxide poisoning in its early stages. Workers should be on the lookout for headaches, dizziness, and lethargy, all of which may indicate unsafe levels of CO in the atmosphere.

Workers who drive lift trucks should practice safe work habits that help decrease emissions, including:

  • Turning off vehicles rather than leaving them idling for long periods
  • Practicing proper driving techniques
  • Reporting concerns about engine efficiency to a supervisor

Employer Responsibilities

OSHA standards require employers to take an active role in addressing any known threats to employee safety – and carbon monoxide is certainly one.

The primary responsibility for the employer is developing a comprehensive health and safety plan to control CO exposure. The plan should detail:

  • Factors contributing to CO in the loading dock
  • Steps to control the hazards and mitigate risk
  • Who is responsible for what
  • How information is communicated to loading dock workers and supervisors

Worker training is also important for being proactive in addressing this issue. By teaching employees about the hazard and how to manage it, you’re empowering them to take their health into their own hands. It also encourages them to look out for one another. Consider posting signs or putting up posters advising workers about the CO hazard, noting the symptoms of CO poisoning, and reminding them of the work practices that decrease emissions in the loading dock area.


Just as everyone plays a part in reducing pollution in our environment, every employee has a role in reducing emissions in the loading dock area. A combination of good work practices (including maintenance), administrative controls, and training will ensure that your employees get the job done safely and your loading dock remains free of harmful concentrations of gases.