OSHA began heightened enforcement of the respirable crystalline silica standard for construction on September 23, 2016. Crystalline silica is one of the most abundant minerals on earth, as it is found in sand, rocks, dust, and dirt. It is also found in products that use sand and aggregates as an ingredient. Only crystalline silica that is less than 10 microns in size is considered by OSHA to be respirable silica. Respirable crystalline silica < 10 micron (µm) is 100 times smaller than beach sand and can’t be seen by the naked eye. This means that it is small enough to be inhaled into the lungs and cause irritation. The rule established an action level of 25 µg/m3 and a permissible exposure limit (PEL) for crystalline silica of 50 µg/m3 over an 8-hour period. This is not a new regulation for construction, this is just an updated standard with tighter limits. In 1966, OSHA created a Special Emphasis Program to Prevent Silica Exposure, subsequently, they established limits in 1970. Back in 1938, The Department of Labor released a black and white film called “Stop Silicosis”. In the film, it describes the hazards associated with silica exposure and the U.S. Department of Labor’s early efforts to ensure safe and healthy working conditions for American workers. On Sept. 12, 2013, OSHA published in the Federal Register a Notice of Proposed Rulemaking (NPRM) for Occupational Exposure to Respirable Crystalline Silica.
Industry is also required to monitor employees for silica exposure under OSHA 29 CFR 1910.1053. We extensively monitor our manufacturing facilities and test the respirable crystalline silica levels per the OSHA requirement, while producing a representative cross-section of our products (including adhesive mortars, self-levelers, grouts, repair mortars, patches, shotcrete mortars, etc.) and have done so for years. Based on testing conducted in closed, non-ventilated, manufacturing workplace conditions, exposure to employees are below the permissible exposure limit of 50 micrograms per cubic meter.
Cement-based, powdered products can be a source of respirable crystalline silica in a work environment when they are poured in the mixing process. Other sources according to the OSHA website: Occupational exposure to respirable crystalline silica occurs when cutting, sawing, drilling, and crushing of concrete, brick, ceramic tiles, stone products, and during tear out. Even sweeping up a jobsite can lead to silica exposure; all activities must be considered when determining an employee’s potential exposure to respirable crystalline silica.
On the jobsite, OSHA requires a written respirable silica Exposure Control Plan (ECP). This is a written plan explaining how you plan on limiting exposure and methods of compliance. You must have a designated “Competent” person on the jobsite, to regularly check jobsites for silica exposure. Everyone on the jobsite should know who the competent person is. You must make silica information available to employees as part of the HAZCOM process. You should know how much respirable, crystalline silica an employee may be exposed to by job. Plan on making engineering controls, use best practice, and/or PPE requirements to stay below the threshold if above. Some best practices can include: Mixing outside, if possible or if mixing inside, adding the powder to the water slowly, pouring from a low height and mixing with a low speed drill until the powder is mixed with the water.
In the last couple of years, I have seen the tile industry trade associations really step up and provide test results and training on best practices and engineering controls. In 2019 at the Coverings show in Orlando, Fla., the NTCA (National Tile Contractors Association) did a great two-part seminar on the respirable silica standard and how to comply utilizing tools commonly used on tile installation jobsites. Back in 2017, the TCNA (Tile Council of North America) and members hired a third-party Environmental Health & Engineering, Inc. for a detailed report on “Exposures to Crystalline Silica and Metals in Ceramic and Glass Tile”. The objective of the research was to provide TCNA members with information relevant to labeling requirements in the State of California per Proposition 65 (Prop 65). Although it was not the specific aim of this research, the analysis is also useful for comparing tile-related exposures to applicable workplace exposure standards, such as the new OSHA crystalline silica rule. It is available on the TCNA website at https://www.tcnatile.com/industry-issues/crystalline-silica-exposure.html.
As a cement-based powder producer, we have done jobsite monitoring with an independent industrial hygienist, testing several of our products that contain up to 75% silica sand (and that are representative of the family of other Mapei products containing silica). These tests were conducted while these products were being poured and mixed with water during an 8-hour period. This data can be used for “objective data” in your Exposure Control Plan when using Mapei powders. Objective data must reflect worker exposures on each shift, each classification, and in each work area. Data, means information such as air monitoring data from industry-wide surveys, or calculations based on the composition of a substance. Additional data is needed, such as, demonstrating employee exposure to respirable crystalline silica associated with a particular product or material, or a specific process, task, or activity. To qualify as “objective,” the data must reflect workplace conditions closely resembling, or with a higher exposure potential, than the processes, types of material, control methods, work practices, and environmental conditions present in the employer’s current operations. A Technical bulletin and lab report are available on our website at http://www.mapei.com/public/US/linedocument/18-1019_Tech_Bulletin_OSHA_Silica_Standard_with_lab_report_lr.pdf.
It is important you understand the regulation and all that is required to comply. The web has plenty of stories of OSHA fines for violating the new regulation. There are many useful documents on the new regulation. I know many large tile companies have structured training programs and silica regulation compliance is typically part of those. Most tile installation companies are smaller and are looking for resources; one document I thought was a great overview of the regulation is on the OSHA website called “OSHA Small Entity Compliance Guide for Construction.” You can also participate in trainings at some tile or flooring industry conventions and some manufacturer’s offer education on the standard too. This article is not intended to cover everything required for compliance of the OSHA Silica regulation. Go to the OSHA website for additional information, bookmark it and review it: https://www.osha.gov/dsg/topics/silicacrystalline/construction.html.