California Silica Rules Headed for Vote
By Emerson Schwartzkopf
SACRAMENTO, Calif. – California’s workplace-safety board will vote this week on proposed emergency regulations to address the increase in silicosis among engineered-stone fabricators.
The new rules, which could take effect this month, will affect any business dealing not only with engineered stone, but with nearly all quarried and manufactured products involving components of stone.
The proposed regulations include equipment requirements, worker health-exam schedules, marking off material work zones, and definitions that encompass almost every action and material used in a fabrication shop.
The state’s Occupational Safety and Health Standards Board will meet in Folsom, Calif., on Thursday (Dec. 14) to consider the regulations. If approved by the board and other state officials, the rules could go into effect by Christmas Eve and remain for at least 180 days.
The regulations – essentially an amendment to current California standards on crystalline-silica hazards – come at the end of a 10-month effort by state workplace-safety agency Cal/OSHA, health officials, industry groups and worker representatives to deal with increased cases of silicosis among fabricators.
The rules also come after four years of worker-health reports and coverage on the issue with media outlets such as National Public Radio and the Los Angeles Times.
The rules can also be used as a basis for permanent regulations, which would require another round of public comments.
The cost of the new regulations, if extended to 10 years, is estimated at $66 million to businesses, with benefits over the same periods totaling an estimated $603 million. Cal/OSHA identified 808 shops in the state that fabricate engineered stone, and a workforce of 4,040.
The meeting will be held at 10 a.m. Pacific Standard Time at the Robert H. Miller III Rotary Clubhouse at 7150 Baldwin Dam Road in Folsom. A live video/audio stream will be available at https://videobookcase.com/california/oshsb/.
The full 19-page text of changes and additions to California’s regulations is available here.
The emergency finding, with a detailed explanation of the process leading to the proposed regulations, is here.
Among the notable changes, with quotations from the proposed changes in italics:
Definition of Artificial Stone
“Artificial Stone” means any reconstituted, artificial, synthetic, composite, engineered, or manufactured stone, porcelain, or quartz. It is commonly made by binding crushed or pulverized stone with adhesives, polymers, epoxies, resins, or other binding materials to form a slab.
The proposed description of the material encompasses most standard quartz-surface products, but porcelain is a puzzling and vague addition. Unlike quartz surfaces, porcelain production uses varying patterns of heat (or sintering) for cohesion, unless one of the material’s components might be seen as a binder.
“High-Exposure Trigger Task”
“High-Exposure Trigger Task” means machining, crushing, cutting, drilling, abrading, abrasive blasting, grinding, chiseling, carving, gouging, polishing, buffing, fracturing, intentional breaking, or intentional chipping of artificial stone that contains more than 0.1 percent by weight crystalline silica, or natural stone that contains more than 10 percent by weight crystalline silica. High-exposure trigger tasks also includes clean up, disturbing, or handling of wastes, dusts, residues, debris, or other materials created during the above-listed tasks.
The proposed description corrals all the steps of fabrication, which then “trigger” the rules concerning crystalline-silica exposure. The only exception is for geologists during field research, who’ll still need respiratory protection.
The definition also specifies the amount of silica, by weight, in both manufactured stone and natural stone for materials to be included under the regulation. More than 0.1 percent will pull in anything defined under the proposed “artificial stone.”
The “more than 10 percent” amount for natural stone will pull in popular materials such as quartzite and granite, so the proposed regulations will effectively apply to any fabrication shop. Some stones are assumed to have 10% or less silica content (such as marble) but that level isn’t uniform.
Respirable Crystalline Silica
“Respirable Crystalline Silica” means quartz, cristobalite, and/or tridymite contained in airborne particles that are determined to be respirable by a sampling device designed to meet the characteristics for respirable-particle-size-selective samplers specified in the International Organization for Standardization (ISO) 7708:1995: Air Quality – Particle Size Fraction Definitions for Health-Related Sampling.
The proposed rules also loop in other sources of crystalline silica besides quartz. Glass isn’t mentioned here as a source; most of it includes amorphous silica that doesn’t crystallize due to rapid cooling during manufacturing. However, a small amount of glass is created using various temperature variations of heat.
Wet Methods
“Wet Methods” means effectively suppressing dust by one of the methods listed below. Regardless of the method used, water must cover the entire surface of the work object where a tool, equipment, or machine contacts the work object.
(A) Applying a constant, continuous, and appropriate volume of running water directly onto the surface of the work object. When water flow is integrated with a tool, machine, or equipment, water flow rates shall equal or exceed manufacturer recommendations and specifications to ensure effective dust suppression.
(B) Submersing the work object underwater.
(C) Water jet cutting (use of high pressure water to cut material).
Manufacturer is ambiguous. It could refer to the producer of the material; however, the mention of tool, machine, or equipment in the same sentence could also refer to producers of those items as the manufacturer.
Demarcation
(A) The employer shall demarcate regulated areas from the rest of the workplace in a manner that minimizes the number of employees exposed to respirable crystalline silica within the regulated area.
(B) The employer shall post signs at all entrances to regulated areas that bear the legend specified in subsection (kj)(23).
Shops will need to physically designate areas where high-exposure trigger tasks will take place. Another part of the proposed regulations limit access to those required by work duties, anyone monitoring air quality, or anyone authorized by OSHA regulations.
Respiratory Protection
Employees performing high-exposure trigger tasks will need to wear a full face, tight-fitting powered-air purifying respirator (PAPR) or a respirator providing equal or greater protection equipped with a HEPA, N100, R100, or P100 filter. For artificial stone, a HEPA, N100, R100, or P100 filter and organic vapor cartridge shall be used.
The proposed rules grant an exception for employees to use a loose-fitting respirator if exposures to silica are below a prescribed level, with air-sampling measurements every six months. However, employees diagnosed with silicosis must use the face-forming mask.
Medical Surveillance
Employers hiring anyone who’ll be exposed to airborne crystalline silica will need to offer a baseline medical exam, including work/medical history, physical exam, chest X-ray, along with pulmonary function and latent tuberculosis infection tests. All of those tests (excluding tuberculosis) will be offered again at least every three years.
