On August 15, 2019, OSHA released a Request for Information (RFI) regarding potential additions to Table 1 of the Respirable Crystalline Silica Standard for the Construction Industry. Employers who implement the control measures specified for the tasks identified in Table 1 are deemed to be in compliance with the permissible exposure limit (PEL), but must assume employees are exposed above the action level.

OSHA is interested in gathering information on additional tasks or equipment and additional engineering and work practice control methods that should be added to Table 1 for both existing and new tasks or equipment. OSHA is also interested in learning if there are “additional circumstances where it would be appropriate” to permit employers covered by the Silica Standards for General Industry and the Maritime Industry to comply with the silica standard for construction. Comments on the RFI are due by October 15, 2019.


OSHA’s silica standards, promulgated on March 25, 2016, establish a PEL of 50 μg/m3 as an 8-hour time-weighted average (TWA), and an action level of 25 μg/m3, calculated as an 8-hour TWA. Employers must ensure that employees are not exposed to respirable crystalline silica (RCS) above the PEL. Except when Table 1 applies, employers must perform exposure assessments of each employee who is or may reasonably be expected to be exposed to RCS at or above the action level. Employers must also provide medical surveillance for employees who are exposed to RCS at or above the action level for 30 or more days per year. In addition, employers must comply with other ancillary requirements that include establishing regulated areas, providing respiratory protection, housekeeping, training, hazard communication, and medical surveillance. The standard also does not apply to employers who have objective data demonstrating that employee exposure will remain below the action level under foreseeable conditions.

For the Construction Industry Standard, employers have the option of either: 1) assessing employee exposures, implementing proper control measures to limit exposures, and verifying they are effective; or 2) for tasks included in Table 1 of the Standard, found at 29 C.F.R. 1926.1153(c)(1), they may implement the control measures prescribed for that task in Table 1. OSHA developed Table 1 to simplify compliance for the construction industry, given the “frequent changes in workplace conditions, such as environment and location.” 84 Fed. Reg. 41667, 41668 (August 15, 2019).

If a General Industry task is indistinguishable from a construction task listed in Table 1, and the task will not be performed regularly in the same environment and conditions, then the General Industry employer can comply with the Table 1 requirements of the Construction Industry Standard.

RFI As an Opportunity for Industry to Expand Tasks on Table 1

Employers who comply with the silica standard by following the specifications in Table 1 are encouraged to comment on the RFI, as are employers who have exposure data to demonstrate that a particular task should be added to Table 1. OSHA published this RFI because it heard from the regulated community that Table 1 should have included additional tasks and because it also recognized the need to periodically update Table 1 to include new control methods: “a static Table 1 could discourage the development of new control technologies for reducing silica exposure.” 84 Fed. Reg. at 41668. In the RFI, OSHA is interested in gathering the following information from stakeholders:

  • Additional exposure control methods not currently listed on Table 1 that could limit exposures from the equipment and tasks listed on Table 1;
  • Additional tasks or equipment not currently listed on Table 1;
  • Stakeholders’ experience with Table 1 controls, including if there are any situations where implementation was infeasible or challenging;
  • Alternative names used by workers or manufacturers to describe the tasks and equipment in Table 1;
  • Economic impacts that could result from expanding Table 1;
  • Whether OSHA should expand the circumstances in which general industry/maritime industry employers should be given flexibility to follow Table 1 of the construction standard when Table 1 tasks are “regularly performed in general industry or maritime in a relatively stable and predictable environment.”

The RFI lists a number of specific questions for stakeholder response. OSHA also welcomes additional exposure monitoring data. If, based on responses to the RFI, OSHA determines that revisions to Table 1 appear appropriate, OSHA will publish a proposed rule for notice and comment.