Confined Space Entry: Hazards, Safety Procedures and Legal Requirements

Quick answer: Confined space work is one of the highest-risk activities in Australian workplaces. Work in or near a confined space is classified as High Risk Construction Work (HRCW) under WHS Regulations, requiring a SWMS, a permit-to-work, and continuous atmospheric monitoring before and during entry.

Last reviewed: March 2026 by the BlueSafe Technical Team. Reflects current Model WHS Regulations.

Confined space work is one of the most hazardous activities in many industries. This guide covers the essential safety procedures for safe confined space entry.

What is a Confined Space?

A confined space is an enclosed or partially enclosed area that:

Is not designed for continuous human occupancy
Has limited or restricted entry and exit
May have an atmosphere that could be hazardous

Common examples include tanks, silos, pits, trenches, sewers, vessels, and storage containers.

Hazards in Confined Spaces

Confined spaces present unique and serious hazards:

Atmospheric Hazards

Oxygen deficiency – Levels below 19.5% can cause impairment or death
Oxygen enrichment – Levels above 23.5% increase fire and explosion risk
Toxic gases – Carbon monoxide, hydrogen sulfide, methane, and others
Flammable atmospheres – Risk of fire or explosion

Physical Hazards

Engulfment by liquids or loose materials
Entrapment in converging walls or equipment
Falls from height or on slippery surfaces
Mechanical hazards from equipment and moving parts
Electrical hazards

Environmental Hazards

Extreme temperatures
Noise
Poor lighting
Difficult communication

Before Entry: Planning and Risk Assessment

Never enter a confined space without proper planning:

1. Is Entry Necessary?

Can the work be done from outside the space?
Can the space be modified to eliminate the need for entry?

2. Risk Assessment

Identify all potential hazards
Consider previous contents and residues
Review adjacent processes that may affect the space
Determine control measures required

3. Permit to Work

Implement a formal permit-to-work system
The permit documents hazards, controls, and approvals
All parties must understand and sign off

4. Emergency Procedures

Plan rescue procedures before entry
Ensure rescue equipment is available and workers trained
Never attempt rescue without proper equipment and training

Control Measures During Entry

Atmospheric Monitoring

Test the atmosphere before entry
Continuously monitor during work
Use calibrated, appropriate gas detectors
Know the action levels for each hazard

Ventilation

Provide mechanical ventilation to maintain safe atmosphere
Never use pure oxygen to ventilate
Position ventilation to effectively circulate air

Isolation

Lock out and tag out all energy sources
Isolate pipework, electrical, and mechanical systems
Use blanking plates or physical disconnection where required

Access and Egress

Ensure safe means of entry and exit
Keep entry points clear at all times
Use appropriate ladders, platforms, or hoisting equipment

Standby Person

A trained standby person must be stationed at the entry point
They must maintain communication with workers inside
They must be able to summon rescue if needed
They must not enter the space to attempt rescue

Emergency Response

If an incident occurs:

Do not rush in – Untrained rescuers become additional casualties
Alert emergency services and rescue team
Ventilate the space if safe to do so
Use supplied air rescue equipment if available
Provide first aid once the casualty is removed safely

Training Requirements

All workers involved in confined space work must be trained:

Hazard identification and risk assessment
Use of atmospheric monitoring equipment
Emergency procedures and rescue equipment
First aid and CPR

Key Takeaways

Confined spaces kill – treat every entry as potentially life-threatening
Always test the atmosphere before and during entry
Never enter without a permit and proper controls in place
Have a rescue plan and trained personnel ready
Consider whether entry is necessary at all

State and Territory Variations

The information on this page is based on the Model WHS Regulations published by Safe Work Australia, which have been adopted (with minor variations) by most states and territories.

Jurisdiction	WHS regulator	Key notes
NSW	SafeWork NSW	Adopted Model WHS Regulations; confined space = HRCW
VIC	WorkSafe Victoria	Uses OHS Act 2004 — confined space requirements under OHS Regulations
QLD	Workplace Health and Safety Queensland	Adopted Model WHS Regulations
SA	SafeWork SA	Adopted Model WHS Regulations
WA	WorkSafe Western Australia	Adopted Model WHS Regulations (2022)
TAS	WorkSafe Tasmania	Adopted Model WHS Regulations
ACT	WorkSafe ACT	Adopted Model WHS Regulations
NT	NT WorkSafe	Adopted Model WHS Regulations

Always verify requirements with your state regulator, as local codes of practice for confined space work may impose additional obligations.

A confined space is an enclosed or partially enclosed area not designed for continuous human occupancy, with limited entry/exit, and a potentially hazardous atmosphere. Common examples include tanks, silos, pits, sewers, and trenches.

Does confined space entry require a SWMS?

Yes. It is one of the 18 HRCW activities under WHS Regulations. A SWMS and a permit-to-work are both required before entry.

What atmospheric tests are required before entry?

The atmosphere must be tested for oxygen levels (safe range: 19.5%–23.5%), toxic gases, and flammable gases. Monitoring must continue throughout the work.

Can I enter to rescue a colleague?

No. Untrained rescuers become additional casualties. Alert emergency services and trained rescue personnel, and use supplied air equipment only if trained and equipped.

Need confined space documentation? Browse our WHS forms for permit templates and checklists.