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Confined spaces

Frequently asked questions

Contents

  1. What is a confined space?
  2. Is there a maximum size area that can be classed as a confined space?
  3. What risks might I be exposed to whilst working in a confined space?
  4. Do I always need an observer?
  5. Does the person on standby need to have the person working in the confined space in sight at all times?
  6. Do we always need a rescue team on hand?
  7. Do I always need a harness?
  8. Can we purge with oxygen to ensure a safe atmosphere?
  9. Do we always need airline respirators?

1. What is a confined space?

Regulation 3.82 of the Occupational Safety and Health Regulations 1996, defines a confined space as an enclosed or partially enclosed space which:

  1. is not intended or designed primarily as a workplace;
  2. is at atmospheric pressure during occupancy; and 
  3. has restricted means for entry and exit;

and which either:

  1. has an atmosphere containing or likely to contain potentially harmful levels of contaminant;
  2. has or is likely to have an unsafe oxygen level; or
  3. is of a nature or is likely to be of a nature that could contribute to a person in the space being overwhelmed by an unsafe atmosphere or contaminant.

2. Is there a maximum size area that can be classed as a confined space?

The size of a space is not one of the factors used to define a confined space.  Therefore, there is no specified minimum or maximum size.

3. What risks might I be exposed to whilst working in a confined space?

A person working in a designated confined space may be at risk of exposure to:

  • electrical shock or electrocution;
  • oxygen deficiency;
  • toxic gases or fumes;
  • engulfment/Suffocation by solids;
  • fire and/or explosion;
  • drowning in liquids;
  • falls from height; and
  • environmental factors such as noise, extremes of temperature, poor lighting, manual handling and radiation.

4. Do I always need an observer?

Yes. A person should be on standby in the immediate vicinity outside the designated confined space.

5. Does the person on standby need to have the person working in the confined space in sight at all times?

As the person on standby has to remain outside the confined space it is not always possible for them to keep the person/s working inside the confined space in sight at all times.

Continuous communication with the worker/s inside the confined space must be maintained. Dependent upon the location, communications may be achieved using:

  • voice;
  • radio (intrinsically safe one if used in flammable conditions);
  • mobile phone (not to be used if flammable gas or vapour is present in sufficient concentration to cause explosion or fire); or
  • hard wired communications.

6. Do we always need a rescue team on hand?

Before work in a confined space begins, a competent person must carry out a risk assessment. The risk assessment must be in writing and take account of the hazards involved; work methods to be adopted; risk factors to be considered and the control measures to be adopted. One of the risk factors to be considered is the arrangement for emergency response procedures including rescue, first aid and resuscitation.

A rescue plan needs to be put in place that can be implemented in an emergency. All necessary equipment that may be required in an emergency (such as harnesses, respirators and stretchers) must be available and serviceable. The relevant members of the emergency response team required to use the equipment must be trained in its use.  The rescue members shall be trained in rescue work including first aid administration. The standby person may form part of an emergency response team by acting as the coordinator but must remain outside the confined space.

7. Do I always need a harness?

Safety harnesses and safety lines complying with AS/NZS 1891.1 should be worn where there is a risk of falling whilst descending into or ascending out of the designated confined space; or where rescue by a direct horizontal or vertical route is possible.

The use of hand operated lifting equipment should be considered, where appropriate, to facilitate the removal of an unconscious person from a confined space.

8. Can we purge with oxygen to ensure a safe atmosphere?

A confined space should never be purged with pure oxygen. Where necessary the confined space should be cleared of contaminants using a suitable purging agent. Gas mixtures used for this purpose should not contain an oxygen content of greater than 21%. Compressed clean air is economical and suitable for use.

9. Do we always need airline respirators?

Supplied-air respiratory protection devices complying with AS/NZS 1716 should be worn when:

  • control measures cannot establish or maintain a safe atmosphere; or
  • the work to be carried out within the confined space is likely to degrade/contaminate the atmosphere, e.g. hot work or painting.

For further information please refer to:

  • Australian Standard AS 2865
  • Regulations 3.82 - 3.87 of the Occupational Safety and Health Regulations 1996; and
  • Occupational Safety and Health Act 1984. 

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