Common risks associated with abrasive blasting include dusts, hazardous chemicals and the use of plant and equipment. Using the following risk management process will allow a person conducting a business or undertaking (PCBU) to consider risks associated with abrasive blasting.
The risk management process involves four steps:
- Identify the problem - this is known as hazard identification.
- Determine the level of risk to workers and others as a result of the problem - this is known as risk assessment.
- Decide what needs to be done about the problem - this is known as risk control.
- Review the risk controls to make sure they are working as planned.
Chapter 2 of the Code provides assistance with each of these steps. In some cases air monitoring and health monitoring may be required - refer to pages 7 and 10 for more information.
The PCBU must share information and consult on decisions where a worker is likely to be directly affected by a work health and safety matter.
Hazards and Control Measures
Prohibited and restricted chemicals
A number of hazardous and carcinogenic chemicals are prohibited for use as abrasive materials. Page 12 of the Code provides information on prohibited and restricted chemicals.
Page 13 of the Code advises that the specific requirements of the Work Health and Safety Regulations 2012 (SA) (WHS Regulations) should be consulted with regards to any materials containing asbestos or lead.
In particular, WHS Regulations 392 to 418 should be consulted when considering lead work, and Chapter 8 on Asbestos.
WHS Regulation 446 prohibits use of a high pressure water spray or compressed air on asbestos or asbestos containing materials. Sampling to test for asbestos should be undertaken by a competent person if there is any uncertainty about the presence of asbestos. The Code of Practice - How to Manage and Control Asbestos in the Workplace and the Code of Practice - How to Safely Remove Asbestos should also be consulted.
Abrasive blasting can generate toxic dust derived from either the blasting medium or the object being blasted.
You should carefully check the labels and Safety Data Sheets that are supplied with the blasting medium to be used. These will contain information on the risks of using that blasting medium and essential control measures. You must also assess the hazardous chemicals that may be released from the surface being blasted and adopt suitable control measures.
Pages 15-22 of the Code outline recommended equipment and technologies for controlling and minimising the generation and discharge of toxic dusts.
As abrasive blasting is a high hazard activity, appropriate personal protective equipment (PPE) should be worn regardless of the other control measures in place. PPE should be well maintained and selected for suitability and comfort. If used, PPE should provide respiratory, head and eye protection, as well as be designed to keep out dust and grit.
Particulate matter is any particle (including water) from either the blasting medium or object being blasted which might strike a worker at high pressure. Common injuries may include eye damage, cuts, burns and skin penetration. In some cases severe injury, including death, may occur.
The risks to workers of being struck by particulate matter should be carefully assessed, particularly where blasting is occurring in a confined space, in an elevated position, or where the operator is not observed by a pot tender able to render emergency assistance should that be required.
The main control measures that might be implemented include:
- isolation of blasting processes from other areas of the workshop
- use of purpose-selected PPE
- use of equipment fitted with a fast, self-actuating cut-off device (a 'dead man control')
- safety training for operators, supported by safety policy.
Refer to pages 23-24 of the Code for more information.
Use of abrasive blasting plant and equipment
The safety of plant and equipment is particularly important as blasting processes are self-destructive by nature of the forces and materials implemented.
When purchasing abrasive plant and equipment you should ensure recommended safety features are incorporated into the design and that you receive from the supplier:
- the manufacturer's manual or information addressing the purpose of the plant
- the results of any testing or analysis
- the conditions necessary for safe use.
The plant should only be used according to the manufacturer's instructions. Chapter 3.4 of the Code provides advice for using particular common types of blasting plant and equipment.
Regular inspection and maintenance by a competent person in accordance to the manufacturer's instructions should be undertaken. In addition, plant and equipment should be checked daily by the operator for wear and damage. A log book with inspection reports, and details of repairs and servicing, should be kept.
Further guidance on plant is available in the Code of Practice - Managing Risks of Plant in the Workplace.
Recycling of blast material
Spent blasting materials may have significant contamination from toxic dust (e.g. lead dust), respirable dust (e.g. crystalline silicon dioxide) or oversized trash.
If this material is to be reused it should be collected by methods that minimise disturbance, such as vacuum equipment. Before reuse, hazardous contaminants should be separated from reusable blasting grains by a cleaning process and filtering equipment. Abrasive materials should not be reused unless it is established by a competent person that the crystalline silicon dioxide level is not greater than the allowed amount.
Recycled waste should be disposed of according to relevant environmental regulations.
Other hazards and control measures
Abrasive blasting processes may generate other hazards associated with noise, heat, vibration, manual handling and working in confined spaces.
The risk assessment process recommended in Chapter 2 of the Code should be used to identify these hazards and develop control measures. Chapter 4 of the Code provides advice on control measures for each of these hazards.
Consideration should also be given to recommendations outlined in the following Codes of Practice: