Silica Sand & Sandblasting: Risks & Safety Suggestions
A question that is often asked is whether you can sandblast with silica sand. While some countries may not have legal rules against it many do and it is highly restricted in the United States and is not considered a very safe blast media. Silica sand whether beach sand, play sand or any type of sand has many more dangers than benefits. However, if you have to use it you want to ensure you follow recommendations to properly control the amount of silica exposure (a requirement by OSHA). This article will cover why silica sand is considered unsafe for sandblasting and what to consider if your thinking about using silica sand for sandblasting to ensure you remain safe and know pertinent safety regulations for blasting with silica sand.
Risks of Silica Sand
Silica sand is a very abrasive material making it effective at quickly profiling a product surface but the problem is that when it hits a products surface it fractures into very tiny particles. These tiny particles are so small that even proper sandblasting respirators are not necessarily sufficient enough to prevent inhalation. Inhalation of silica sand causes scarring of the tissue around the inhaled particles which ultimately results in scarring of the linings of air the lungs air sacs. There are a variety of types of silicosis including acute, chronic, and accelerated. Each ultimately ends up in lung damage that is irreversible. Additionally, silica is a known carcinogen. Due to all of these dangerous side effects silica sand is not safe for sandblasting. You can learn more about silicosis here and the dangers of silica here.
Symptoms of silicosis vary depending on the type you experience Acute silicosis results in fluid in the lungs which can cause low oxygen levels, cough, weight loss, and even chest pain. Chronic silicosis results in swelling in the lungs and accelerated silicosis also results in swelling but at a faster rate. Simply put silicosis is dangerous and life threatening.
You may wonder how can silicosis still be problematic if I am wearing a proper respirator. The problem is that there is chance of exposure even after being finished blasting, while cleaning up blast media, and even during blasting. The fragments become so small which is why blasting with silica sand is not safe. OSHA instituted guidelines requiring silica sand levels to be highly controlled which are required to be in place as of 2017. These requirements can be hard to properly achieve. The CDC has a strong recommendation that silica sand be banned while OSHA has implemented strict requirements for controlling the amount of silica sand exposure which are required to be met.
What If I want to use Silica Sand?
If knowing the potential dangers that are associated with sandblasting with silica sand and you still need to consider blasting with silica sand then you will want to thoroughly review the requirements set forth by OSHA. You will also need to conduct air monitoring if using silicosis to confirm what if any additional recommended safety controls will be required. To meet their requirements you will have to implement proper engineering controls and/or safety equipment. Proper Engineering controls would involve having ventilation and other requirements to keep the amount of exposure below 50 micrograms per cubic meter of air in an 8 hour shift as of 2017 but these recommendations could change. OSHA recommends a few steps that can help but ultimately you will have to confirm you have properly controlled silica sand exposure with OSHA. OSHA does offer free on site consultation which may be able to help you have a thorough plan of addressing safety concerns related to blasting with silica sand.
Safety Recommendation 1 – Silica Sand Substitution
The first line of defense against silica that OSHA recommends is the substitution for another blast media. Below you will find alternatives to Silica sand.
What alternatives are their to Sandblasting with Sand
A variety of blast medias can be used in place of sand to sandblast and are much safer to use. Some options that are often used include crushed glass, coal slag (mineral blast media), or even steel medias if you want to recover blast media.
Safety Recommendation 2 for blasting with silica sand – Isolation and Containment
If substitution is not an option the next recommendation by OSHA to reduce risk of silicosis when sandblasting with sand is to consider isolation and containment. Practically speaking this means that the silica sand is kept away from others. This can be achieved through a blast room with dust collection that meets code requirements or a sandblast cabinet with proper dust collection. Each solution that you may consider you would want to verify that it meets OSHA’s requirements and ensure that you have strong policies in place to reduce the number of workers near the cabinet or blast room. This guide helps with additional details on sandblast room ventilation In addition to the blast room ventilation you need a proper blast hood respirator as required by OSHA 1910.94, a blast hood respirator is significantly different than dust masks as it will have positive pressure and meet all pertinent blast safety requirements.
Safety Recommendation 3 – Administrative Controls
In addition to considering substitution and isolation / containment you OSHA recommends considering administrative controls to reduce silica sand exposure. Some of the potential administrative controls you can consider include things like:
- Being mindful of blowing silica sand outside of containment areas – this can include having policies of not using compressed air during clean up as well as using containment devices to prevent migration of silica sand
- Scheduling work with sand when the least possible number of workers are present
- Having environmental rules that prevent blasting if there is increased risk of silica sand migration
- Having Strong clean up guidelines dictating proper clean up equipment and technique is used to prevent silica dust from being disturbed, this could involve using a hepa certified vacuum or similar solution.
- DO not allow for eating near blast areas due to risk for inhalation
Final Thoughts and Additional Resources Related to Sandblasting with Silica Sand
Ultimately silica sand is a dangerous blast media given its potential to cause significant harm to one’s health. Ideally substituting silica sand for a different safer blast media is ideal. If you still are going to use silica sand you want to ensure you coordinate with OSHA to verify the amount of silica that is being generated, that it is within suggested limits, and if it is not that you follow proper options to control silica sand. In addition to the respiratory safety of sandblasting there are other safety requirements that you should consider which are well addressed by this OSHA guide to blasting safety.