Updated: Dec 16, 2019
We have a bad habit… and we all need to address the elephant in the room.
No. you can not use actual sand in a sandblaster... EVEN IF YOU ARE OUTSIDE.
THE ISSUE IS FREE CRYSTALLINE SILICA.
When air blasting technology hit the market place, the obvious choice for this application was sand. It was plentiful, inexpensive, and got the job done; however, what was happening on the micron level was unknown at the time. When a high-velocity particle of sand impacts a substrate it will pulverize on contact releasing a basic component of soil... quartz, cristobalite, or tridymite, which are common forms of free silica. The resulting microscopic silica particle becomes airborne and respirable, and when inhaled will affect the alveoli of the lungs, creating a condition known as silicosis. Alveoli act as sites for the exchange of oxygen and CO2 to our bloodstream and as silica particles are inhaled, the alveoli become irritated, scarred, and eventually cease to exchange critical gases with our blood, starving our body of oxygen resulting in hypoxia, pulmonary disorders, and other critical body-system failures. OSHA regulates the intake of respirable crystalline silica to an action level of 25 μg/m3 (micrograms of silica per cubic meter of air), averaged over an 8-hour day (OSHA 1910.1053(b)). This silica particle is so small, that even when blasting outside, the area of influence will hold particles in suspension, dropping only 1 meter per 24 hours in windless conditions creating a respirable cloud of dust affecting anyone who comes in contact with it, aware or unaware of what you have just exposed them to.
BUT GLASS IS MADE FROM SAND
Heating sand to 3090° Fahrenheit will cause silicon dioxide to melt and change its natural crystalline structure to something that can be referred to as an amorphous solid. This transformation eliminates “free silica” and cannot pulverize to particle sizes on the same level as silica in the naturally occurring crystalline state. In fact - NIOSH (The National Institute for Occupational Safety and Health (NIOSH), recommends glass bead as an alternative to silica sand.
WEAR A RESPIRATOR.
You should never be breathing in concentrated levels of dust, whatever and wherever it may be. Air supplied, positive pressure respirators should be worn in any dust intensive processes. Buyer & operator beware… an air-supplied respirator system needs to be certified with all components conforming to NIOSH specifications. This includes hoses, filters, fittings, CO monitors and any auxiliary equipment that may be operating in this setup all the way to the compressor hookup. We have found that best practice is to source all breathing air equipment from one manufacturer to ensure your breathing air system works properly and effectively.
BOTTOM LINE (sensitive readers - we’re about to be blunt)
Blasting with sand is dangerous and is resulting in irreversible injury and deaths from un-informed operators and bad business practices. There is an abundance of alternative abrasives to choose from, so please inform and educate. Here are other alternatives to sand with many other benefits including abrasive profile benefits, strip rate increases, and reusability.
Please stay safe. Our team is here to help. If you have any questions about blasting practices or if you think your process needs to be looked at - our sales engineers will gladly come onsite to walk through everything with you. Please do not hesitate to reach out!