Sheet Metal & Air Conditioning Contractors’ National Association


OSHA Announces New Standard for Silica

On March 24, 2016, the Occupational Safety and Health Administration announced a final rule to improve protections for workers exposed to respirable silica dust.  The final rule is written as two standards, one for construction and one for general industry and maritime.  For the construction industry, and affected SMACNA contractors, potential silica exposures are found in tasks that include drilling and cutting silica-containing materials such as concrete and stone.  For SMACNA contractors, a typical task affected by this rule would be setting duct and pipe hangers into concrete.  In general industry, potential silica dust exposures are found in manufacturing and foundry operations where silica and related products are commonplace.  Most employers can limit harmful dust exposure by using equipment that is widely available – generally using water to keep dust from getting into the air or a ventilation system to capture dust where it is created.

The final rule includes the following general provisions:

  • Providing greater certainty and ease of compliance to construction employers – including many small employers – by including a table of specified controls they can follow to be in compliance, without having to monitor exposures.
  • Reducing the permissible exposure limit for crystalline silica to 50 micrograms per cubic meter of air, averaged over an eight-hour shift.
  • Requiring employers to use engineering controls (such as water or ventilation) and work practices to limit worker exposure; provide respiratory protection when controls are not able to limit exposures to the permissible level; limit access to high exposure areas; train workers; and provide medical exams to highly exposed workers.

Employers covered by the construction standard have until June 23, 2017 to comply with most requirements. Employers covered by the general industry and maritime standard have until June 23, 2018 to comply with most requirements.

SMACNA will be providing compliance assistance materials in the coming weeks. In the meantime, the OSHA silica webpage has current information including a fact sheet for construction.  A great resource to help develop a silica dust control plan for each project can be found at  For additional information. contact Mike McCullion, SMACNA director of market sectors and safety, at 703-995-4027 or