Preventing carbon monoxide poisoning from LPG-powered floor cleaners

What is carbon monoxide?

Carbon monoxide (CO) is a colourless, odourless and tasteless gas which interferes with the ability of the blood to carry oxygen and can affect the heart and central nervous system. Prolonged exposure to high concentrations of CO can cause unconsciousness or death. Headaches, nausea, dizziness and lethargy are early symptoms of CO over-exposure.

LPG-powered floor burnishers and buffers

LPG-powered floor burnishers or buffers are commonly used to polish floors in workplaces. Their exhausts can generate high levels of carbon monoxide which can quickly accumulate in small, poorly ventilated spaces or areas.

The workplace airborne exposure standard for CO, set by Safe Work Australia, is an 8-hour average of 30 ppm (parts per million) of air.

Safe Work Australia also has guidelines for short-term CO exposure above the eight-hour time-weighted average. The guidelines for the control of short-term carbon monoxide exposure are:

• concentration of 200 ppm, total exposure 15 minutes
• concentration of 100 ppm, total exposure 30 minutes
• concentration of 60 ppm, total exposure 60 minutes

A concentration of 400 ppm should never be exceeded.

Recommended control measures

Employers, including self-employed people, have a duty under the Occupational Health and Safety Act 2004 (OHS Act) to eliminate or reduce risks to health and safety, so far as is reasonably practicable. Using electric-powered cleaning equipment instead of LPG-powered can eliminate the risks associated with exposure to carbon monoxide from LPG-powered cleaning equipment.

If it is not reasonably practical to use electric-powered equipment, an employer or self-employed person should ensure:

• The LPG-powered equipment is fitted with a closed-loop engine emission system to minimise CO emissions and maintain emissions at safe levels, regardless of the load on the machine. This system should shut down the engine when the pre-set CO level is exceeded.
• A qualified gas fitter maintains the LPG-powered equipment, in line with the manufacturer's instructions, to minimise CO emission levels.
• All LPG-powered equipment operators are trained in the risks and symptoms associated with CO over-exposure, the importance of not adjusting the machine’s fuel system and of ensuring regular maintenance to minimise CO emissions.

Operators may also use suitable CO monitors to warn them when CO levels are unsafe or to check that the equipment is functioning safely. They should be trained in how to use and read the monitor and what to do if they detect unsafe CO levels.