22 FEATURE
Correct procedure: ventilation and purging Mechanical purging is the best option to ensure the area is safe – opening the cover of the space alone is not enough as some gases are lighter than air( such as methane), while others settle lower and will not escape the area easily, such as carbon monoxide.
Best practice would be to use a mechanical high pressure pump / fan to pump oxygenated air into the space, where:
• A pump / filter unit is outside
• Filtered air is pushed through a large hose into the confined space
• The hose is placed in the space first, then the area is purged for a set time
As for how long the area needs to be ventilated before entry, there is no fixed universal time – a risk assessment will need to be conducted on the area to provide ventilation time.
Coetzee states that ventilation and oxygenation would be the one golden rule that he feels could decrease the risk to plumbers of methane.“ Ensure the area is well ventilated and has enough oxygen. Don’ t rely on your own senses.”
Methane and the OHS Act The OHS Act does not have dedicated categories such as‘ confined spaces’ or‘ working at heights’, but it provides general health and safety requirements that ensure no risk is placed upon employees.
It is open to interpretation on purpose, so each company must:
• Look at its own scope of work
• Identify all risks
• Attach relevant regulations
This means that before working in the space, the company needs to have a risk assessment done. This directly refers to Section 8.2( d) of the OHS Act( duty of the employer), which states that the employer must ensure that they know all the risks and hazards associated with any work performed.
Zoshua Colah | Unsplash. com
The general rule of thumb is that confined spaces are regulated by government.
July 2026 Volume 32 I Number 05