Ozone exposure

Background

A laundry within an aged care facility uses an ozone generator to clean clothes and sheets in cold water, killing bacteria and viruses

Employees working within the laundry noticed a bleach-like odour, not knowing it was ozone, and reported the smell to maintenance.

Maintenance attended the laundry several days later and noted one of the ozone generators had tripped and was leaking ozone into the washing machines. They were advised to reset the generator.

The odour continued to grow stronger, and employees were advised to clean out the washing machines.

Two employees were overcome by the ozone gas and suffered adverse health effects including a sore throat and light headedness. Several other employees, including contractors, were also exposed to ozone.

Safety issues

Potential health effects from exposure to ozone

• Irritation and inflammation of eyes, nose, throat and lower airways. May cause:
  • coughing
  • sore and scratchy throat
  • uncomfortable feeling in chest
• Reduced lung function, not able to breathe as deeply or strongly as usual.
• Heightening of asthma and chronic respiratory diseases. Including chronic bronchitis, a form of chronic obstructive pulmonary disease or COPD.
• Increased susceptibility to respiratory infections.
• May continue to damage lungs when symptoms have disappeared.

Exposure Standard

Ozone has a peak limitation for its exposure standard. A peak limitation exposure standard is the maximum concentration of a substance in the air that a worker can be exposed to over the shortest period of time that it can be measured. The measurement period cannot be more than 15 minutes. In Australia, for ozone, the peak limit is 0.1 parts per million (ppm) (0.2 mg/m3).

Recommended ways to control risks

• Buy or fit ozone generators with alarms and controllers to shut off automatically if there’s a leak.
• Set up a system to monitor and alert for high ozone levels.
• Perform regular maintenance as recommended by the manufacturer.
• Train all relevant employees about how to use machines with ozone generators. This should include information about hazards and what to do if ozone is detected.

Legal duties

Under the Occupational Health and Safety Act 2004, employers must, so far as is reasonably practicable, provide and maintain a working environment that is safe and without risks to the health of employees (including independent contractors). Where risks cannot be eliminated, so far as is reasonably practicable, they must be reduced so far as is reasonably practicable.

Employers must also ensure, so far as is reasonably practicable, that persons other than employees are not exposed to health and safety risks arising from the employer's undertaking.

Employers must provide employees with the necessary information, instruction, training or supervision to enable them to do their work in a way that is safe and without risks to health.

Employees must take reasonable care for their own health and safety at work, and the health and safety of others who may be affected by their acts or omissions at a workplace.