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Last month, OSHA published a list of Frequently Asked Questions (FAQs) and answers surrounding its silica standard. Developed with input from industry and union stakeholders, the document provides additional guidance to employers and employees regarding the standard’s requirements for general industry, which has presented a number challenges for some due to the rule’s complexity.

Those covered by the standard are encouraged to review the full FAQs to improve their understanding of their compliance obligations under the silica standard. Below, we take a look at a few of questions and answers OSHA provides.

Exposure Assessments: Does the standard cover employees who perform silica-generating tasks for only 15 minutes or less a day?

The standard does not include a specific exemption for tasks with only short-term exposures (e.g., tasks with exposure for 15 minutes a day or less). However, the standard does not apply where the employer has objective data demonstrating that employee exposure to respirable 3 crystalline silica will remain below 25 μg/m3 as an 8-hour time-weighted average (TWA) under any foreseeable conditions. Short-term silica exposures must be very high in order for those exposures to reach or exceed 25 μg/m3 as an 8-hour TWA; for example, if an employee is exposed for only 15 minutes, his or her exposure would have to be higher than 800 µg/m3 for that 15-minute period before the 8-hour TWA exposure would be at or above 25 μg/m3. See 81 Fed. Reg. at 16706. Some examples of tasks that could generate very high short-term exposures include abrasive blasting and grinding engineered stone counter tops, which are typically associated with high levels of visible dust.

Workers may perform maintenance tasks involving occasional, brief exposures to silica that are incidental to their primary work. Provided that these employees perform these tasks in isolation from activities that generate significant exposures to silica, and perform them for no more than 15 minutes throughout the work day, their exposures will usually fall below the AL of 25 µg/m3 as an 8-hour TWA under all foreseeable conditions. When employers obtain or develop objective data showing that exposures will remain below the AL under any foreseeable conditions, these employees will not be covered by the standard.

Regulated Areas: If employees could be exposed above the permissible exposure limit (PEL) in a given area, but no employees actually enter the area, or work in the area for a long enough period of time that it would be reasonable to expect their 8-hour TWA exposures to exceed the PEL, does the employer need to establish a regulated area?

No. The term “regulated area” is defined as an area where an employee’s silica exposure exceeds, or can reasonably be expected to exceed, the PEL. See 29 C.F.R. § 1910.1053(b). If an employer has, and adequately enforces, work rules precluding employees from entering a particular area, then the employer does not need to treat that location as a regulated area. Furthermore, an area does not need to be designated as a regulated area if the employer has and enforces work rules limiting employees’ time in the area so that there is no reasonable expectation that their 8-hour TWA exposures will exceed the PEL. OSHA notes, however, that if one or more employees will enter the area long enough that it is reasonable to expect their 8- hour TWA exposures to exceed the PEL, the employer must establish a regulated area and all employees entering the area must wear respirators (even those not in the area long enough for their exposures to exceed the PEL). See 29 C.F.R. § 1910.1053(e)(4).

Methods of Compliance: Are employers permitted to use administrative controls to comply with the PEL?

Yes. Administrative controls, which are a type of work practice control, are an acceptable means of reducing employee exposures under 29 C.F.R. § 1910.1053(f)(1). For example, an employer could schedule high-exposure tasks to be conducted when employees are not working in adjacent areas. The standard does not prohibit the rotation of employees (a type of administrative control) to limit employee exposures. However, OSHA discourages this practice as a means of avoiding implementation of engineering and other work practice controls. It can be administratively difficult to maintain employees’ exposures at or below the PEL solely using rotation. Moreover, the use of rotation may require the employer to provide medical surveillance to additional workers and to train many workers on multiple jobs.

Written Exposure Control Plan: Does the standard require employers to list all of the tasks that could involve any exposure to silica in their written exposure control plans?

No. Tasks that are not covered by the standard, e.g., because the employer has objective data demonstrating that employee exposures will remain below the AL under any foreseeable conditions, do not need to be included in the written exposure control plan.

The full silica FAQ document is available on OSHA’s website.

Let VelocityEHS Help!

Need help complying with the requirements of the silica rule? VelocityEHS’ Chemical Management Solutions can help you track substances in your inventory containing silica so you can have a foundation for planning your exposure assessments, use of controls, and employee training.

Contact us to find out more about the ways we can help you maintain compliance with the silica rule, improve your EHS management, and keep the workplace safe for your entire workforce.