March 25, 2016 the long awaited OSHA rule for crystalline silica hit the street with an effective date of June 23, 2016. The actual implementation date is June 2017 for construction and June 2018 for general industry and maritime. There are some exceptions and caveats, but by and large, it’s June 2017 and June 2018.
What is Silica?
Before we dive into the nitty gritty of the standard, let’s take a look at silica. Silica is a naturally-occurring mineral used in many industrial applications and can be found in various common household products. It can be synthesized (made in a lab) or mined. There are many types and forms of silica; some are more harmful, some are less. Silica mining has enjoyed a boom in demand in recent years due to hydraulic fracking.
Crystalline silica is a special type that is particularly hazardous from a respiratory perspective. You’ve undoubtedly seen (and touched) crystalline silica many times. If you’ve been to a rock exhibit and seen the quartz rocks or geodes, you’ve seen crystalline silica. You’ve also touched silica if you’ve taken a walk on the beach. Yes – the sand on most beaches is silica.
What is the Health Concern with Silica?
Almost everyone has either handled a quartz rock or a geode, walked along a beach, or played in a sandbox and has lived to tell the story. Although this is a true statement, it doesn’t tell the story about what’s going on with silica and the hazards with silica exposure. As with most lung hazards (particle lung hazards in particular), the real hazard is with the fine particles – the ones you don’t see. In this case, the particle size of concern is in the 10 micron (micrometer) diameter range or 10 thousandths of a millimeter in diameter. This is about one thousand times smaller than what we can normally see.
As with most particles (e.g., asbestos, hexavalent chromium, lead, arsenic), it’s the fine particles that get in your lungs that cause the problem which is why you don’t have a concern with the beach sand or the rock exhibits – the particle size is too big. It isn’t until we get down to the 10 micron size that there’s a health risk. Particles this small make it to the lungs and cause a condition called silicosis. Silicosis is a scarring of lung tissue due to the irritating effects of the micro fine silica fibers. It is the silica version of asbestosis. Particles bigger than 10 microns never make it to the lungs but get caught by our nose and throat.
Don’t worry, OSHA isn’t going to make you wear respirators on beaches or at the rock exhibit. Their concern is the 2.3 million workers (of which 2 million are construction) exposed to the fine crystalline silica particles, and preventing the 100 annual deaths due to silica exposure. Though the mortality rate of silica-related deaths has been reduced by 90% in the last 50 years1. 100 deaths per year is 100 more than necessary because it is 100% preventable.
Part 2 – Silica Frequently Asked Questions
- Centers for Disease Control and Prevention, Weekly Mortality and Morbidity Report, 2/13/15, Silicosis Mortality Trends and New Exposures to Respirable Silica – United States, 2001 – 2010.