THE COHEN GROUP
  Environmental Health & Safety Consulting Services

The Cohen Group Newsletter - Volume 19  Issue 1, Article 2.  January 2008

 
The New Proposed Cal/OSHA Standard on Exposure to Concrete/Masonry Dust
By Mark Golembiewski, CIH

If you work in the construction industry or the building trades, you’ve probably heard something about the recent regulatory efforts in California to control construction worker exposures to silica dust.  Cutting, drilling, coring, and grinding concrete or masonry materials are all common work activities that can release respirable silica dust.  In response to a 2006 legislative bill, SB 46, which would have prohibited nearly all dry-cutting or grinding of masonry materials, Cal/OSHA formed an advisory committee to address the issue and has developed a proposed standard as a regulatory solution.  

A new section of the Construction Safety Orders, §1530.1, “Control of Employee Exposures from Dust-Generating Operations Conducted on Masonry or Concrete Materials,” would apply to the use of powered tools or equipment to cut, grind, core, or drill concrete or masonry materials.  The proposed standard was published in October 2007 with a public comment period that ended with a public hearing before the Cal/OSHA Standards Board on December 13.  A copy of the proposed rule and the Board’s justification for the proposal (‘Statement of Reasons’) can be found at:  http://www.dir.ca.gov/oshsb/concreteandmasonry0.html.  The Board asserts that “the impetus for proposing this standard is the widespread recognition that these operations have…probably the greatest potential of the operations conducted in construction settings to generate overexposure to silica dust when the dust generated by these operations is not controlled.”

The new rule would essentially require the use of water or local exhaust ventilation, together with appropriate training, to control dust exposures when workers perform the regulated tasks using power tools.  The Standards Board acknowledges that these protective measures are already widely used within the construction industry, but states that the “proposed standard is intended to provide a means to enforce the use of this practice [engineering controls] by all employers so that all employees and employers are equally protected from those employers who take insufficient action to prevent overexposure.”

The relatively brief proposed rule provides a definition of the concrete and masonry materials to which it applies, including brick, clay brick, concrete block, natural and manufactured stone, tile, and terra cotta.  However, the rule would not apply to stucco, plastering materials, wall cladding, siding, or other similar products.  Several work activities are also exempted, including jack-hammering that is incidental to plumbing or landscaping activities, work with powder-actuated tools, other incidental work such as drilling holes for plumbing fixtures, and cutting tile backer board with shears.  The proposed “performance” standard does not specify the control method to be used.  Instead, it only requires that “a dust reduction system shall be applied to effectively reduce airborne particulate” and that procedures are implemented “to ensure that dust reduction systems maintain their effectiveness for dust reduction throughout the work shift.”  A notable exception is that a dust reduction system is not required for roofing operations involving roofing tiles, pavers, or similar materials.  The key caveat, however, is that a dust reduction system is not needed if the employer can reliably demonstrate by applicable air sampling data that the operation does not result in employee exposures exceeding the Cal/OSHA PELs, particularly for crystalline silica.

The standard also contains an employee training component that would apply to all employees assigned to jobs or work areas where the regulated operations are conducted.   The required employee training topics are listed in the standard. Additional training is required for supervisors to ensure they understand the employee work tasks that could result in exposure and the procedures for implementing the control measures selected by the employer to control those concrete or masonry dust exposures.

Currently, it appears that the proposed rule will become final, possibly without any further changes.  However, one member of the Standards Board raised objections to the proposal at the December public meeting, as did other construction employer representatives who commented.  They believe that any operations which generate dust in excess of the Cal/OSHA exposure limits are already regulated by the existing standards and it is not clear what added benefit will result from the new rule.  Concerns were also raised about the additional costs to employers, particularly from the air monitoring that would need to be performed.  The Cohen Group is actively involved in this proposed action and will provide further updates on the status of this new rule as information becomes available.