Hazards of Abrasive Blasting Materials
Abrasive blasting uses compressed air or water to direct a high velocity stream of an abrasive material to clean an object or surface, remove burrs, apply a texture, or prepare a surface for the application of paint or other type of coating. Employers must protect workers from hazardous dust levels and toxic metals that may be generated from both the blasting material and the underlying substrate and coatings being blasted. This fact sheet provides information on abrasive blasting material, health hazards, and methods to protect workers.
Abrasive Blasting Materials
The decision to use a certain type of abrasive material can depend on factors such as cost, job specifications, environment, and worker health.
Commonly used abrasive materials:
- Silica sand (crystalline)
- Coal slag
- Garnet sand
- Nickel slag
- Copper slag
- Glass (beads or crushed)
- Steel shot
- Steel grit
- Specular hematite (iron ore)
Alternative, less toxic blasting materials include:
- Ice cubes
- Dry ice
- Plastic bead media
- Sodium bicarbonate (baking soda)
- Ground walnut shells, ground corn cob, & other biodegradable material
- High pressure water
Abrasive blasting operations can create high levels of dust and noise. Abrasive material and the surface being blasted may contain toxic materials (e.g., lead paint, silica) that are hazardous to workers.
- Silica sand (crystalline) can cause silicosis, lung cancer, and breathing problems in exposed workers
- Coal slag and garnet sand may cause lung damage similar to silica sand (based on preliminary animal testing)
- Copper slag, nickel slag, and glass (crushed or beads) also have the potential to cause lung damage
- Steel grit and shot have less potential to cause lung damage
- Slags can contain trace amounts of toxic metals such as arsenic, beryllium, and cadmium
How to Protect Workers from Exposure to Abrasive Blasting Materials
Each abrasive blasting operation is unique, involving different surfaces, coatings, blast material, and working conditions. Before beginning work, employers should identify the hazards and assign a knowledgeable person trained to recognize hazards and with the authority to quickly take corrective action to eliminate them. Use engineering and administrative controls, personal protective equipment (PPE), including respiratory protection, and training to protect workers involved in abrasive blasting activities. Engineering controls, such as substitution, isolation, containment, and ventilation are the primary means of preventing or reducing exposures to airborne hazards during abrasive blasting operations. Administrative controls, including the use of good work and personal hygiene practices, can also reduce exposure. When engineering and administrative controls cannot keep exposures to hazardous materials below OSHA permissible exposure limits, respiratory protection must be used.
- Use a less toxic abrasive blasting material
- Use abrasives that can be delivered with water (slurry) to reduce dust
- Isolation and Containment
- Use barriers and curtain walls to isolate the blasting operation from other workers
- Use blast rooms or blast cabinets for smaller operations
- Use restricted areas for non-enclosed blasting operations
- Keep coworkers away from the blaster
- Use exhaust ventilation systems in containment structures to capture dust.
Perform routine cleanup using we methods or HEPA filtered vacuuming to minimize the accumulation of toxic dusts.
- Do not use compressed air to clean as this will create dust in the air
- Clean and decontaminate tarps and other equipment on the worksite
- Schedule blasting when the least number of workers are at the site
- Avoid blasting in windy conditions to prevent the spread of any hazardous materials
Personal Hygiene Practices
- Prohibit eating, drinking, or using tobacco products in blasting areas
- Provide wash stations so workers can wash their hands and face routinely and before eating, drinking, or smoking
- Vacuum or remove contaminated work clothes before eating, drinking or smoking
- Provide accommodations for end-of-shift showers and change areas with separate storage facilities for street clothes, protective clothing and equipment
- Keep contaminated clothing and equipment out of the clean change area.
An abrasive-blasting respirator must cover the wearer’s head, neck, and shoulders to protect the wearer from rebounding abrasive. Workers must use only respirators approved by NIOSH to provide protection against dusts produced during abrasive-blasting operations.
- Type CE NIOSH-certified blasting airline respirator with positive pressure blasting helmet.
Support personnel involved in cleanup and other related activities may also need respiratory protection.
Personal Protective Equipment
- Hearing protection
- Eye and face protection
- Leather gloves that protect to full forearm and aprons (or coveralls)
- Safety shoes or boots
Worker Training and Hazard Communication
- Provide training to abrasive blasters and support personnel on blasting health and safety hazards, how to use controls, personal hygiene practices, safe work practices and the use of PPE and respirators
- Manufacturers are required to include appropriate health hazard information on the blasting materials on safety data sheets (SDS) as required under OSHA’s Hazard Communication standard (29 CFR 1910.1200)
- Obtain and read the manufacturer’s SDS for health hazard information on the abrasive material you are using