Revised February 2022
Information and Resources on Silica
What is crystalline silica?
It is one of the most abundant substances on earth, and is commonly found in sand, rock, stone, brick, tile, concrete and mortar. High levels of inhalation exposure have been linked to cancer and silicosis, a potentially fatal lung disease. OSHA estimates that over 2.3 million workers are exposed to this substance in the workplace. Exposure to silica in the construction industry can be caused by activities such as but not limited to cutting, drilling, grinding, sanding, or polishing of these materials.
OSHA
Federal OSHA issued a new final rule in March 2016 that reduces the permissible exposure limit (PEL) for respirable crystalline silica (RCS) drastically, from 250 µg/m3 (construction) or 100 µg/m3 (general industry), to a PEL of 50 µg/m3 and an action level of 25 µg/m3. Enforcement of the new limits in the construction industry began September 23, 2017. OSHA expects compliance with this rule will result in the prevention of approximately 900 new cases of silicosis annually. On February 4, 2020, OSHA published new instructions regarding a National Emphasis Program (NEP) to target industries expected to have the highest exposure to RCS.
Compliance Overview
As part of a workplace compliance program, each employer with employees expected to be exposed above the Action Level of 25 µg/m3 is required to prepare a written silica exposure plan. The plan must speak to a number of issues, including how the employer will demonstrate compliance with the new rules at the job site. A key component of that part of the plan will be to ensure all instructions provided by equipment and accessory manufacturers are followed. This will help ensure a product is being used correctly to minimize RCS exposure.
When it comes to specific methods of compliance, there are a few options. These include:
◦ For construction, Using a Table 1 compliance solution. The OSHA code provides information as to specified engineering controls for 18 different applications that OSHA accepts as adequately reducing RCS exposure. Examples of Table 1 solutions include using wet cutting methods or using a commercially available dust extractor that utilizes a 99% efficiency filter, a filter cleaning mechanism and, for grinder applications, has a minimum flow rate of 25 CFM/in of grinding wheel diameter.
◦ Use of Objective Data. Data supplied by manufacturer or third‐party source may be used to demonstrate employees are under the PEL for the given application. The test conditions must be equal to or more challenging than actual job site conditions and the data must show exposure will be below the PEL or include instruction on PPE (personal protective equipment) that is required.
◦ Use of a Scheduled‐Monitoring Program. This type of program requires job site testing to determine individual exposure(s). Helpful Links:
▪ OSHA's Silica Information: https://www.osha.gov/silica-crystalline
▪ OSHA's Silica Rule Information Page (including link to Table 1): https://www.osha.gov/silica-crystalline/construction#tableOneTasks
▪ OSHA regulation 1926 construction pertaining to silica: https://www.osha.gov/laws-regs/regulations/standardnumber/1926/1926.1153
▪ OSHA regulation 1910: General industry pertaining to silica: https://www.osha.gov/laws-regs/regulations/standardnumber/1910/1910.1053
▪ Center for Construction Research and Training's Work Safely with Silica: http://www.Silica-Safe.org
State-run OSHA programs may have more stringent requirements than noted above. Please refer to your state site for further information.