Working with dry ice

Background

A pathology lab received a shipment where dry ice had been placed inside a sealed container with the specimen. The production of carbon dioxide gas in the airtight container caused a rapid pressure build up and the container exploded.

No injuries occurred in this incident but the explosion damaged a ceiling tile and pipe under a sink. Decontamination of the area was required.

Safety issues

Explosion

Dry ice (solid carbon dioxide) becomes carbon dioxide (CO2) gas at room temperature, with 1kg of dry ice expanding to 760 litres of CO2.

If dry ice is stored in a sealed container, as the temperature increases so does the pressure inside the container until a failure of the packaging occurs.

Failure of the packaging may result in injuries from fragmentation or pressure waves.

Asphyxiation

Carbon dioxide gas is colourless and virtually odourless. It is heavier than air and may accumulate in confined spaces.

If dry ice is stored or handled in areas with poor ventilation, CO2 accumulation can lead to:

• dizziness
• headaches
• difficult breathing
• loss of consciousness, or
• death by asphyxiation.

Temperature

Skin contact with dry ice can cause frostbite and damage to skin cells.

Recommended ways to control risks

• Never place dry ice inside a container that is airtight.
• When preparing specimens for transport, dry ice must be placed outside the airtight container and inside ventilated packaging, such as a polystyrene box with visible venting holes.
• Use transparent soft packaging for the specimen where possible (e.g bio-pouches) to enable visual checks and reduce projectile risk.
• Prior to dispatch ensure dry ice is easily identifiable with the correct dangerous goods labels and dangerous good documentation attached. (see infographic below)
• Ensure safety data sheets are up to date and available to employees, contactors and emergency services personnel.
• Store dry ice receptacles in a dry well-ventilated area away from areas of heavy pedestrian traffic, emergency exits and protected from impact.
• Provide appropriate personal protective equipment for employees working with dry ice including gloves and eye protection.
• Provide adequate information, instruction and training in relation to the hazards associated with dry ice and its safe use, handling and storage.
• Have policies and procedures for working with dry ice including what to do if you suspect a container has become pressurised, such as segregating, evacuating and initiating emergency responses.
• Ensure emergency management procedures are in place for areas where dry ice may be in use including spill containment and first aid processes.

Legal duties

Occupiers of premises where dangerous goods are stored and handled have duties under the Dangerous Goods Act 1985 and the Dangerous Goods (Storage and Handling) Regulations 2022. These include:

• Identifying any hazards associated with the storage and handling of dangerous goods at the premises, having regard to what the occupier knows or ought reasonably to know about the hazard.
• Ensuring that any risk associated with the storage and handling of dangerous goods at the premises is eliminated, or if it is not reasonably practicable to eliminate the risk, is reduced so far as is reasonably practicable.

Under the Occupational Health and Safety Act 2004 (OHS Act), employers and self-employed persons have duties which they must fulfil so far as is reasonably practicable. These duties include the following:

• Providing and maintaining a work environment that is safe and without risks to health.
• Ensuring persons other than employees are not exposed to risks to their health and safety from the employer’s conduct.
• Consulting with employees and any HSRs when:
  • Identifying or assessing hazards or risks at the workplace.
  • Making decisions about risk control measures at the workplace.
  • Proposing changes to the workplace, plant or work processes that may affect health and safety.