You may have just finished up a major renovation project in your home or office and have been left with a huge amount of construction dust as an unwanted byproduct. Maybe you have seen news stories on the dangers of silica dust and worried “is it in my home?”. In this blog, I will go over a few facts about silica, specifically respirable crystalline silica (RCS). I’ll also describe who should be worried about exposure, and cover a few of the health concerns associated with RCS.
What is Crystalline Silica?
The specific concern associated with silica is a specific form, crystalline silica. Silica is a naturally occurring mineral found in the earth and is commonly found in building materials such as concrete, stone, sand, and mortar. Crystalline forms (vs. amorphous forms) get their name from the word “crystal” and have a lattice structure that can lead to particles that are more harmful to health. What we are worried about specifically is respirable crystalline silica, the size of particles that can be inhaled deep into the gas exchange region of your lungs. Silica can be found all around your environment naturally, for example, a large portion of the sand you find at the beach is silica. Before you go running away from your nice beach vacation, remember that since these particles are much too large to be inhaled deep into your lungs they do not pose the same health risk as respirable particles.
Exposures to Crystalline Silica
So how do crystalline silica particles become small enough to enter your lungs? The main exposure risk comes from activities that cut, grind, and polish crystalline silica-containing materials. When materials are disturbed in this way, a plume of very small particles is released into the air and if workers are not taking the correct precautions, they can possibly be exposed. There is no exposure risk when the materials are undisturbed in your home. Almost all of the resources related to RCS exposure are focused on workers, not the general public. This is because the general public typically would not be exposed to RCS on a day to day basis. There may be exposure concerns for people who perform DIY projects that disturb crystalline silica-containing materials (i.e. cutting or crushing stone, brushing old mortar joints, etc). There are also concerns when laundering clothes worn by someone who works with silica, or if people are home when a contractor is doing work that may disturb silica.
Silica can cause a range of health effects. Chronic health effects include silicosis, a scarring of the lung tissue due to silica, and lung cancer. Silicosis also makes people more susceptible to lung infections such as tuberculosis.
Working With Silica
A very useful resource for easily determining what kind of protection and clean-up is needed when working with crystalline silica materials is OSHA’s “Small Entity Compliance Guide for the Standard for Respirable Crystalline Silica for Construction”. This guide includes 18 common tasks and the recommended controls and personal protective equipment to be worn. If you have hired a contractor, they should be following these rules to protect their workers as well as assuring that clean-up is performed correctly so your family is not exposed.
RCS’s exposure risk is at the highest during the act of disturbing the materials. That means it is best to test while the worker is doing the cutting, grinding, etc into the crystalline silica-containing materials. Unfortunately, we typically get calls from concerned clients after the project is done, and also after clean up. This makes it very hard for us to test retrospectively. Although a lab could analyze for the presence of crystalline silica in settled dust, this doesn’t provide a concentration of the respirable crystalline silica, which is the concern. It is best to try to predict if there may be RCS exposures and arrange for testing to occur during the work.
If you have concerns with potential respirable crystalline silica exposure or any other air quality concerns in your home, please reach out to us.