Page 82 - Occupational Health & Safety, July 2018

RESPIRATORY PROTECTION
Respirable CMrystalline Silica: Regulations and Considerations
BY GREG ZIGULIS any people have heard of changes to the (cement and brick, asphalt/pavement, china and ce- OSHA respirable crystalline silica (RCS) ramics, dental supplies, steel and foundry industries), regulations and know that the OSHA hydraulic fracturing processes, and other sources. You “compliance” dates vary based upon in- can find out if products of potential concern contain
dustry. However, not everyone may have had a chance to follow the topic closely. If your company conducts work that may result in employee exposures to RCS that could exceed the OSHA Action Level (25 μg/m3 on an eight-hour time weighted average basis), the following paragraphs present an overview of relevant points and share some program considerations.
Why the Revised Standard?
OSHA believes that employees exposed to respirable silica at the permissible exposure limit (PEL) set in the old standard faced “a significant risk of material impairment to their health.” It estimated that there are 2 million construction workers and 300,000 in general industry and maritime workers impacted. The poten- tial health effects that can result from certain levels of exposure might be surprising:
(Courtesy of Dr. Ken Rosenman, Michigan State University College of Human Medicine)
Various industries have argued “against” the ap- propriateness of the revised standards for feasibility and other reasons, but OSHA’s opinions have pre- vailed in court.
What is Respirable Crystalline Silica and Where Is it Found?
Silica (silicon dioxide/SiO2) can exist in crystalline or non-crystalline form. The standard is intended to provide protection from exposures to the crystalline form, when it exists in or is made into an especially small size, referred to as “respirable.” “Respirable” particles are those of a size (approximately less than 10 μm) that when inhaled have the potential to reach the deeper regions of the lung. OSHA-required expo- sure assessments must be conducted with respirable particle size selective samplers meeting International Organization for Standardization (ISO) 7708:1995.
α-Quartz is the most abundant crystalline form and is found in sand, sandstone, shale and granite. Other forms listed in the standards are cristobalite and tridymite. Within general industry, RCS exposures may be created from abrasive blasting, manufacturing
or may contain crystalline silica by consulting indus- try publications, reviewing safety data sheets, com- municating with manufacturers and/or conducting laboratory tests.
Regulatory Status
The Federal standard for respirable crystalline silica in construction (29 CFR 1926.1153) is already in effect. Many construction-related organizations have devel- oped information tools either for their membership or the public, many of which can be easily found on the Internet. This includes Associated General Contrac- tors of America (agc.org), the Center for Construction Research and Training (https://www.silica-safe.org/), and others.
The General Industry version of RCS standard, (29 CFR 1910.1053, Respirable Crystalline Silica) seems to have received less attention to date, perhaps since it has an OSHA compliance date (June 23, 2018, with certain exceptions) that is later than that for construc- tion, and due to litigation against OSHA. Some or- ganizations have held off on implementing the new standard, hoping that the standard would be over- turned or changed. However, all but one element of a key lawsuit that had been at the U.S. Court of Appeals for the D.C. Circuit has been upheld, with only one item sent back to OSHA for further evaluation. (This one item pertained to the lack of a medical removal provision in the standard.)
The result: While there could be a delay in compli- ance obligations dates, at least the bulk of the standard will remain in effect, including impactful requirements.
Some Highlights from the GI Standard
The general industry standard includes, among other things:
■ Revised exposure limits. The new Action Level (AL) and Permissible Exposure Limit(PEL) for re- spirable crystalline silica are 25 μg/m3 and 50 μg/m3, respectively. Companies that “used” to be compliant may no longer be.
■ More detailed requirements to conduct expo- sure assessments (initial as well as periodic if dictated by prior monitoring and also triggering events).
■ The establishment of “regulated” areas with specifically worded DANGER signs where exposures may exceed the PEL.
■ Requirements that employers use engineering and work practice controls to reduce exposures to be- low the PEL, and until they do, to provide respiratory protection.
Non-Malignant
Malignant
Alveolar Proteinosis (Acute Silicosis)
Lung Cancer
Parenchymal Fibrosis (Silicosis)
Tuberculosis
Connective Tissue Disease
Chronic Renal Failure
COPD
76 Occupational Health & Safety | JULY 2018
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