The Invisible Dangers in Enclosed Spaces

carbon monoxide dangers in enclosed spaces

It is common knowledge that moving forklifts can kill, but so can those gas or fuel-powered engines that are left idling and producing the poisonous gas carbon monoxide. In fact, these can be the silent killers. 

Carbon monoxide exhaust fumes

Carbon monoxide (also known by its chemical formula, CO), being tasteless, colourless and odourless, is undetectable by our senses, which makes it very dangerous. Carbon monoxide fumes are produced by the forklifts burning of fuel such as gas, diesel, or propane. When forklifts are used indoors there can be a build-up of high-level concentration of carbon monoxide in the atmosphere that can affect the health of workers and others in and around any confined area.

The exhaust fumes from liquid petroleum gas (LPG), petrol, and diesel engine forklifts contain carbon monoxide. This gas can rapidly build up in indoor areas and people can quickly become unconscious. Carbon monoxide poisoning can cause permanent brain and heart damage and in serious cases death.

Carbon monoxide is generated when carbon is burning, but burns incompletely, this occurs in internal combustion engines. Breathing it in poses many serious health complications, if not death. The common symptoms of poisoning include mild headache, nausea, and dizziness followed by vomiting. The longer you are exposed, the worse symptoms you may have such as stomach pain and difficulty breathing.

Prolonged exposure to even small levels of carbon monoxide can result in different neurological conditions such as forgetfulness, mood swing, and depression and in other cases, trouble in concentrating and making logical decision.

carbon dioxide safety

Carbon monoxide poisoning in an industrial setting

In August 1998, 75 workers at an Iowa plastics plant attended work as usual, not suspecting they were any danger. As they worked during three consecutive 8-hour shifts, some began to feel headachy, others sick in other ways.  By the end of the third shift, nearly half the workforce developed similar symptoms. Ten workers were ill enough to be taken to the hospital.

Investigations revealed that the two forklift trucks with propane-powered propulsion systems, driven in the work area about their normal rounds were found to be emitting some 40,000 parts per million (ppm) of odourless, tasteless, colourless carbon monoxide from their exhaust pipes. The safe guideline for CO emissions is as little as 1/20th of that amount.

The plant’s air-conditioning system had been shut down for servicing, and an exhaust fan had malfunctioned, reducing the effective ventilation rate. However, the forklifts emitted such excessive amounts of carbon monoxide that no practical level of ventilation could have maintained concentrations below recommended exposure limits. ** Neither workers nor managers were aware that the symptoms they experienced were related to carbon monoxide poisoning, which delayed recognition and response.

While forklifts are known to cause many deaths and serious injuries through crashes and crush accidents, carbon monoxide poisoning from propane, gasoline, or LPG-powered lift trucks can be just as deadly. The danger exists when gas-powered trucks are used in enclosed, or even partially enclosed spaces. All fuel-burning engines produce some carbon monoxide, but in road vehicles, complex pollution control systems can convert much of it into far less harmful substances.

The Invisible Dangers in Enclosed Spaces »

Risk Management Strategies for operators

Given that forklifts have various types of systems and are powered by fuels such as gas, diesel and propane, the responsibility for reducing the hazard falls to the operators. Some of the risk management strategies that can be implemented are as follows:

  • Avoiding the use of the forklift indoors: These include both totally enclosed spaces, such as factory buildings or warehouses, and somewhat covered spaces, such as supply sheds. Some experts recommend electric powered trucks for indoor use.
  • Where forklifts must be used indoors, provide adequate ventilation: Ensure that the ventilation can maintain carbon monoxide concentrations below recommended exposure limits.
  • Avoid idling: Even outdoors, and especially near windows or vent openings where exhaust gas can be sucked into occupied spaces. In fact, forklifts really should be shut down except when they’re actually being used, a practice that also saves fuel.
  • Keep the engine serviced: Well-maintained engines burn fuel more efficiently, reducing the carbon monoxide released into the exhaust.
  • Add a catalytic converter: This is the system modern cars use to greatly neutralise emissions. With claims that emissions can be cut as much as 99 percent. Other systems, such as closed-loop carburetion, can improve this further.
  • Think about converting to compressed natural gas: CNG is less polluting than LPG or propane. One downside: You will need a special filling apparatus to refuel.
  • Test your exhaust: This is done with a carbon monoxide analyser. Some experts suggest a test every day a forklift is used.
  • Consider a new truck: They have far more efficient engines than older models.

These risk management strategies are additional to the general operator’s training which is essential as they have a responsibility to ensure that they are following the workplace safety procedures and the manufactures instructions.

In addition, it’s paramount that other workers too are aware and able to identify the signs and symptoms of carbon monoxide poisoning, and what actions are required if they think it’s happening. 

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