By: Thomas H. Welby Published: May 2016

OSHA's New Final Rule on Silica Dust

After a long and somewhat contentious public comment process (that included 14 days of public hearings, and the receipt of more than 2,000 comments totaling more than 34,000 pages of material) OSHA has issued its final rule (with standards for the construction industry and for general industry/maritime) to limit employee exposure to respirable silica.

The final rule takes effect on June 23, 2016, after which construction industry employers will have one year to comply with the rule’s new, more stringent provisions.

The new rule is the culmination of a yearlong effort to cut employee exposure to respirable silica for the first time since OSHA was first enacted in 1971.  It can be read in its entirety at www.federalregister.gov/articles/2016/03/25/2016-04800/occupational-exposure-to-respirable-crystalline-silica.

The dangers of silica have been recognized going back at least to the 1930s, at which time U.S. Secretary of Labor Frances Perkins convened a panel of experts and stakeholders to determine the best ways to protect workers from it.  OSHA estimates that approximately 2.3 million American workers are exposed to respirable crystalline silica in the workplace.  These include about 2 million construction workers who drill, cut, crush or grind silica-containing materials such as concrete and stone, and some 300,000 workers, in a wide range of general industry operations, ranging from brick manufacturing, sandblasting, foundries, and hydraulic fracturing (a/k/a/ fracking) to glass manufacturing, dental laboratories, and jewelry production.  The inhalation of tiny particles of silica can lead to silicosis, an incurable and sometimes fatal lung disease, as well as lung cancer, chronic obstructive pulmonary disease, and kidney disease.

In construction, silica exposure can occur during such common tasks as using masonry saws, grinders, drills, jackhammers, and hand-held powered chipping tools; operating vehicle-mounted drilling rigs; milling; operating crushing machines; and using heavy equipment for demolition or other tasks.

The construction standard does not apply, it should be noted, where exposures will remain low under any foreseeable conditions.  Examples of tasks to which the standard does not apply include mixing mortar, pouring concrete footers, slab foundation and foundation walls, and removing concrete formwork.

Typically, the main line of defense against silica inhalation involves controlling dust with water or a vacuum system, or the use of respirators, where wetting down surfaces and vacuums are insufficient or impracticable.    The main reason why standards are being tightened is that the ones in place are based on research dating back to the 1960s, and silica exposure at levels currently permitted was found to cause lung cancer and kidney disease.  A secondary reason for the new standards is the expansion of new industries, including fracking and stone and artificial stone countertop manufacturing, that entail worker exposure to silica.

The new rule, therefore, reduces sharply — from 250 to 50 μg per cubic meter of air (averaged over an 8-hour shift) — the “PEL” (permissible exposure limit) for respirable silica.  Further, they require employers to:

  • Use engineering controls, such as water or ventilation, to ensure that the PEL not be exceeded;
  • Provide respirators, when engineering controls do not suffice to limit exposure;
  • Restrict access to  high-exposure areas;
  • Develop a written exposure control plan;
  • Designate a “competent person,” to implement the written exposure control plan;
  • Offer medical exams (including chest x-rays and lung function tests) to workers required by the standard to wear a respirator for 30 or more days per year;
  • Train workers on silica risks, and how to limit exposure; and
  • Keep records of both workers’ silica exposure, and medical exams.

Opposition to the new standards was mounted by groups, including the Associated General Contractors of America and the American Chemistry Council.  Generally, opponents of the new measure maintain that, by more energetically enforcing the existing standards, new silicosis cases could be brought down to almost zero, and that OSHA has greatly underestimated the costs to businesses to implement the new rules.

OSHA claims to have made numerous adjustments in formulating its final rule, with both special flexibility for the benefit of the construction industry, and detailed guidelines as to how workers performing common construction tasks can be protected.  Employers are given a choice between control methods spelled out in Table 1 to the construction standard, and measuring worker exposure and then deciding independently which dust controls work best in their workplaces to keep silica exposure below the PEL.

For example, workers using a hand-held power saw to cut silica-containing materials can, pursuant to Table 1, use a saw equipped with an integrated water delivery system that continuously feeds water to the blade.  If the worker uses the saw outdoors for four hours or less per day, no respirator would be needed.  If the worker uses the saw indoors for any length of time, or outdoors for more than four hours, he or she would need to use a respirator with an “assigned protection factor” of 10 or greater.  A NIOSH-certified facepiece respirator that covers the nose and mouth (sometimes referred to as a dust mask) could be used.  If the worker needs to use a respirator on 30 days or more per year, he or she would need to be offered a medical exam.

Continuing with our example of a hand-held saw, an employer electing not to use Table 1 would have to measure the amount of silica to which workers are exposed, if the same may be above an “action level” of 25 μg per cubic meter of air, averaged over an 8-hour day.

Workers must then be protected from respirable crystalline silica exposures above the permissible exposure limit of 50 μg/m3 (averaged over an 8-hour day).  Dust controls should be used to keep silica exposures below the PEL or, if dust controls do not do the job, respirators should be used instead.

OSHA estimates that, once the new measures are fully in effect (the rules are being phased in over a five-year period) they will prevent approximately 900 new cases of silicosis, and save about 600 lives, each year.

OSHA, by the way, has a number of special programs aimed at helping employers (especially small and medium-sized businesses in high-hazard industries, which describes, I think, many of the readers of this series).  Among these are OSHA’S On-Site Consultation Program, which offers free and confidential help in identifying workplace hazards, advice on complying with OSHA standards, and assistance in improving safety and health management systems.  On-site consultation services are separate from enforcement, and do not result in penalties or citations.  More information is available at www.osha.gov.dcsp/smallbusiness, or by phoning (800) 321-6742.

© Welby, Brady & Greenblatt, LLP.
All Rights Reserved. By visiting this site, you agree to our Terms of Service. For more information please read our Privacy Policy Attorney Advertising