Abrasive blasting general health and safety issues

Abrasive blasting can kill or cause permanent injury and illness.

Lung damage, hearing loss, tinnitus, eye damage and severe lacerations are just some of the injuries people working in this industry can receive. Fatalities can occur from inhaling carbon monoxide in the breathing air produced by combustion of compressor oil or motor exhaust fumes entrained in the compressor air intake.

Prohibition on sand blasting

Abrasive blasting with materials containing more than 1 per cent free crystalline silica including river sand, beach sand or other white sand, also called sand blasting, is prohibited in Queensland workplaces.

Blasting media that can be used instead of sand includes:

• garnet
• crushed glass
• glass bead
• metal shot
• aluminium oxide
• granulated plastic
• some metal slags (although some may contain high levels of lead and chromium which may present other health, safety and environmental risks).

Do not use abrasive blasting media that contains the following restricted hazardous chemicals:

• Materials with any radioactive substances where the level of radiation exceeds 1 becquerels per gram, so far as is reasonably practicable.
• Materials containing more than
  • 0.1 per cent antimony
  • 0.1 per cent arsenic
  • 0.1 per cent beryllium
  • 0.1 per cent cadmium
  • 0.5 per cent chromium (except as specified for wet blasting)
  • 0.1 per cent cobalt
  • 0.1 per cent lead (or which would expose the operator to levels more than those set out in Part 7.2 of the Work Health and Safety Regulation 2011)
  • 0.1 per cent nickel
  • 0.1 per cent tin
• Any substance that contains chromate, nitrate or nitrite.

Plant, equipment and machinery

The plant, equipment and machinery used in abrasive blasting should be checked daily for wear and damage by the operator. Owners of machinery and equipment should keep log books and inspection check sheets containing a full history of service and repairs.

Information on how to use the following plant, equipment and machinery safely can be found in abrasive blasting, plant and equipment section of the Abrasive blasting code of practice 2021 (PDF, 1.13 MB).

Personal protective equipment (PPE)

Personal protective equipment (PPE) protects workers against the hazards which can affect workers through different ways. PPE can include:

• an air-line positive pressure hood or helmet
• protective suits or clothing to keep out dust and abrasive grit
• chemically resistant gloves, safety boots and aprons
• barrier cream (for short term protection).

Supplied air quality

Air supplied to an abrasive blaster's helmet from a compressor must meet certain standards for breathability. Industrial compressors used for blasting air should not be used to supply breathing air as it may produce poor quality breathing air.

Requirements include:

• at least 170 litres per minute of continuous cool air
• oxygen content between 19.5 and 22 per cent
• carbon monoxide less than 10 parts per million
• oil less than 1 mg per cubic metre
• carbon dioxide less than 800 parts per million
• removal of excess water vapour.

Air compressors used for breathing air should have the following safety features installed to prevent carbon monoxide poisoning or death:

• a continuously operating carbon monoxide monitor equipped with an alarm on oil-lubricated compressors in a position as close to the user as practicable
• a high temperature protection cut off switch on oil-lubricated compressors, where available from manufacturers. The high temperature protection cut off circuit should be connected in such a manner that it is fail safe. For example the compressor will not start if there is a wire disconnected or a sensor fails.

The following safe procedures and processes should also be followed:

• Supply a breathing air system that is designed for safe use with supplied-air respirators.
• Periodically test the air quality.
• Place the compressor air intake well away from sources of contaminants, particularly exhaust gases from operating plant, equipment or vehicles, or areas where exhaust fumes may accumulate.
• Establish and maintain a comprehensive respiratory protection program for the use of helmets and hoods. The program should include information about how to safely manage sources of air for air-supplied respirators.
• Perform scheduled, periodic inspections and maintenance by a competent person on all equipment to ensure it is continuously maintained in safe operating condition. For example:
  • Carry out a daily visual inspection of respiratory protective equipment (RPE) and breathing air systems, including the compressor, to identify potential problems.
  • Fix any identified problems immediately or remove the faulty equipment from service until it is repaired.
  • Schedule maintenance in accordance with the manufacturer's instructions.
  • Calibrate carbon monoxide monitors as recommended by the manufacturer.
• Develop and implement written safe work procedures that provide workers with adequate information about the hazards and risks related to the work and the control measures implemented. This should include information on:
  • risks associated with the use of compressed air for breathing air
  • selection, use and maintenance of RPE and breathing air system
  • use and maintenance of alarms and monitors.

A carbon monoxide monitor equipped with an alarm is recommended as a back-up. There is no filter generally available to remove carbon monoxide from supplied breathing air.

Housekeeping

Drift from abrasive blasting can be harmful not only to workers but also to members of the public. Good housekeeping can minimise the risk of exposure.

While other control measures should prevent dust escaping from the area where blasting is being done, any dust or residue that does make its way into the workplace should be cleaned as soon as practical after blasting has finished.

Where practical, accumulated dust should be removed using:

• wet methods, such as low-pressure hosing or wet-sweeping
• an industrial vacuum cleaner rated for use with hazardous dust that meets the requirements of L class, M class or H class as described in AS/NZS 60335.2.69:2017 Household and similar electrical appliances - Safety - Particular requirements for wet and dry vacuum cleaners, including power brush, for industrial and commercial use (IEC 60335.2.69 ED 5, MOD).

Dry sweeping and/or compressed air should never be used to clean up accumulated dust from abrasive blasting processes.

Confined spaces

The person in control of a business or undertaking must identify any hazards associated with working in a confined space. Typically they may arise when blasting walls inside tanks, vessels or silos.

The primary hazards commonly found in confined spaces are:

• lack of oxygen
• toxic gases, vapours or fumes
• flammable gases, vapours or fumes
• engulfment
• mechanical equipment.

Related links

• Abrasive blasting code of practice 2021 (PDF, 1.13 MB)
• Carbon monoxide in breathing air during air compressor use