Abrasive blasting (or sandblasting) in a safe manner requires an understanding of the equipment and media being used and the actual process. Blasting involves propelling fine, abrasive particles (media) under pressure at high speed at a surface. The amount and composition of media, the dust generated by the process and the area where the blasting is taking place are both important considerations.
Of course, media containing free silica such as sand should never be used. Many alternatives to sand exist and can often provide better results and more value over the span of an entire project. Almost all media will generate some contaminants in the air such as nuisance dust which would not generally be classified as a acute exposure issue. Protecting the operator from dust inhalation and skin damage would be the primary concerns.
Each type of blasting media has a different fracture rate and will generate different levels of dust. If a consumable (high fracture rate) type media such as Crushed Glass Grit or coal slag is being used, significant amounts of dust can be generated. Proper inhalation protection is required such as dust masks or even fresh air fed helmets. Be sure to factor the surface conditions being blasted when considering the amount of dust. Surfaces that are heavily rusted will produce significant amounts of dust unrelated to the blast media being used versus ‘clean’ surfaces that are simply being etched to prepare for painting.
Perhaps the most important issue is the area where the blasting is taking place. If done in an open environment, the risk of inhalation is decreased but care must be taken to avoid contamination to the environment immediately surrounding the blast area. If in an enclosed area, air fed helmets and proper exhaust is almost always necessary.
No matter where the blasting is being done, wearing proper protective clothing is always required. Leather gloves and coveralls will minimize skin exposure to the abrasive blast process. A leather blast suit will further protect the body from injury.