What Makes a Silo a "Confined Space" ?
Under the Work Health and Safety Regulation 2011, a confined space is an enclosed or partially enclosed area that:
- Is not designed for continuous human occupancy
- Has restricted entry and exit
- Has a risk to health and safety from hazards
Grain silos, by definition, meet all three criteria.This classification triggers a comprehensive set of legal requirements under AS 2865: 2009 "Confined Spaces" that must be followed for any entry—including for cleaning.
The Fatal Risks of Silo Entry
Silos present multiple life - threatening hazards:
1. Engulfment
The most common cause of silo fatalities.Grain can behave like quicksand—a worker standing on top can sink within seconds if the grain is flowing or disturbed.Once chest - deep, the pressure makes breathing impossible even before burial is complete.
2. Atmospheric Hazards
- Oxygen deficiency: Grain respiration and decay depletes oxygen
- Toxic gases: Fumigants (phosphine), CO2, and nitrogen from decay
- Combustible atmosphere: Grain dust at explosive concentrations
3. Mechanical Hazards
- Augers and sweep arms inside the silo
- Unexpected activation of filling or emptying systems
☠️ Grim Statistics
Grain silos have a higher fatality rate than almost any other confined space.In America, about 20 silo deaths occur annually.Australia has seen multiple fatalities in recent years.Most victims are experienced workers—familiarity breeds complacency.
Mandatory Control Measures Under AS 2865
- Risk Assessment: A competent person must identify all hazards before entry
- Entry Permit: Written authorisation specifying controls and precautions
- Atmospheric Testing: Before and during entry—oxygen, combustibles, toxics
- Isolation: Lockout/tagout of all mechanical systems and product inlets
- Ventilation: Purge toxic atmospheres before entry
- Rescue Plan: Documented emergency procedures, practiced regularly
- Standby Person: Someone outside, in continuous communication, NEVER to enter
- Training: All entrants must hold current confined space certification
ProSan Australia's Silo Entry Protocols
Our confined space team includes:
- Confined Space Entry Supervisors with current certification
- Rescue - trained standby personnel
- Calibrated 4 - gas atmospheric monitors
- Tripod and harness retrieval systems
- Communication equipment for all entrants
We never allow bottom-entry for unblocking. All material is dislodged from top-entry using Whiphead technology or pneumatic lances.
When to Call a Professional
DIY silo cleaning is not worth the risk.If your silo needs internal access for:
- Hang - up or blockage removal
- Interior cleaning or inspection
- Maintenance or repair work
Call a specialist with confined space capability. Contact ProSan Australia for safe silo services across Queensland.