OSHA has delayed enforcement of its new silica standard until September 23, 2017, citing a need to conduct additional outreach and provide educational materials and guidance for employers. The agency should devote some of this extra time to developing additional guidance related to the standard’s performance option.

OSHA’s silica standard outlines two main compliance options – controlling exposures using Table 1 or choosing between two alternative methods (the performance option and scheduled sampling). Compliance for the Table 1 and scheduled sampling options is pretty straightforward in the standard. For the most part, Table 1 requires commercially available tools with integrated ventilation or water systems designed to control or capture dust at the source. Table 1 also outlines the specific conditions when employees must wear respirators. For scheduled sampling, the standard provides an “if/then” guide detailing the sampling schedule for tasks above the permissible exposure limit (PEL) and action level (AL).

However, the current guidance available for the performance option is much less clear. According to the standard, under the performance option, employers must “assess the 8-hour time-weighted average (TWA) exposure for each employee on the basis of any combination of air monitoring data or objective data sufficient to accurately characterize employee exposures to respirable crystalline silica.” Beyond that, the standard itself notes that “OSHA has not included specific criteria for implementing the performance option in the rule.”

Let’s say a contractor has sampling data showing silica exposures are slightly above the PEL when using a Hudson water sprayer as a dust control for a handheld saw. Giving workers N95 respirators or limiting the task to a few hours should be enough to keep exposures below the PEL. It would seem that a contractor could opt out of Table 1 and use this alternative control method under the performance option of the standard.

However, according to a top OSHA official, this method would NOT be in compliance since it’s less protective than the control method listed in Table 1 for that task. This is because the performance option only allows for respirator use “after implementing all feasible controls.” Although both examples above protect the employee below the PEL, the Table 1 option allows the employee to work without a respirator, essentially proving that it’s feasible to do so. In short, any alternative control method must be as good or better than the control methods listed in Table 1.

Although not spelled out in the standard, this issue of feasibility makes Table 1 the required compliance method in the silica rule. Any task or operation in Table 1 (and their associated controls) is what other compliance methods will be measured against. To opt out of Table 1:

• It must be infeasible to comply with Table 1
• The task or operation must not be represented in Table 1, or
• The alternative control method must be as protective as Table 1 options

Contractors who choose the performance option must support their choice with sampling and/or objective data. But as we discussed in last month’s article, objective data is both hard to find and requires the contractor to make very subjective determinations about workplace conditions. Two well-meaning people could disagree on whether the equivalent data is appropriate for the current situation. Unless OSHA identifies objective data repositories, using objective data won’t reduce a contractor’s need to perform sampling. In the absence of recognized objective data, sampling data will have to be thorough and well-documented.

At this point, following Table 1 is the best method to ensure compliance with the rule. When Table 1 is infeasible, any alternative control option should be supported with detailed sampling data and proof of infeasibility.

For more information about compliance with the silica rule, visit the Fund’s silica page or call the OSH Division at 202-628-5465. The Fund’s Silica and Table 1 and Controlling Silica Exposures in Construction publications are available for order in our online Publications Catalogue. OSHA’s Controlling Silica Exposures in Construction guide also provides additional information.

[Walter Jones is the LHSFNA’s Director of Occupational Safety & Health.]