OSHA Crystalline Silica Rule Compliance

In 2016, the U.S. Occupational Health and Safety Administration (OSHA) created a new standard to address the problem of respirable crystalline silica (RCS) dust control in the construction industry. Enforcement of the standard began nationally on September 23, 2017, with varying degrees of compliance enforcement emphasis by region and state.

OSHA’s maximum penalties, which had not been adjusted in over two decades, were increased by 81% in 2017. Going forward, the agency will continue to adjust its penalties for inflation each year based on the Consumer Price Index. The 2018 penalty for the first violation can be up to $12,934 per violation. These new rules apply to the construction, oil and gas, general industry, and maritime operations where jackhammering, drilling, cutting, sawing, blasting, and crushing of materials such as concrete, rock, brick, stone, and mortar can result in the inhalation of airborne microscopic silica particles. This can result in severe health complications for workers, including silicosis, lung cancer, COPD, and kidney disease.

OSHA established a different mandatory compliance date for this standard for each industry:

- Construction: September 23, 2017
- General Industry and Maritime: June 23, 2018
- Oil & Gas Industry Hydraulic Fracturing Operations: June 23, 2021

States that operate their own Occupational Safety and Health Plans are required to adopt maximum penalty levels that are at least as effective as that of the Federal OSHA.

What is Crystalline Silica and What are the Risks from Exposure?

Crystalline silica is an abundant material found in the earth’s crust. Silica is a common component of building materials such as block, brick, ceramic tiles, concrete, mortar, rock, sand, soil, stone, and many other natural and man-made materials used in construction and demolition projects, and in other related industries.

Occupational exposure to respirable crystalline silica occurs when high-energy operations such as breaking, chipping, crushing, cutting, drilling, hammering or sawing are applied to these construction materials. During these processes, hazardous RCS particles—sometimes one hundred times smaller than ordinary grains of sand—are released into the air, where they may be inhaled by workers on site. These particles can embed themselves deep into the lungs and cause chronic disabilities, health problems, and even death.

OSHA Silica Standard for Construction Industry

OSHA's RCS Standard applies to all occupational exposures to respirable crystalline silica in construction work, except where employee exposure will remain below 25 μg/m3 (25 micrograms per cubic meter of air) as an 8-hour time-weighted average (TWA) under any foreseeable conditions.

Exposures to respirable crystalline silica occur when tools such as the ones listed below are used on natural or man-made construction materials that contain crystalline silica:

Chipping tools, handheld, power
Crushing machines
Drilling rigs, dowel and vehicle-mounted
Drills, core, rig-mounted
Drills, handheld and stand-mounted (including impact and rotary hammer drills)
Grinders, walk-behind, and handheld
Jackhammers
Milling machines, drivable and walk-behind
Saws, core, rig-mounted
Saws, drivable and walk-behind
Saws, handheld, power
Saws, stationary, masonry
Heavy equipment and utility vehicles are used to abrade or fracture silica-containing materials during demolition activities and for tasks such as grading and excavating

Exposures also occur during tunneling operations, during abrasive blasting when sand or other blasting agents containing crystalline silica are used, or when abrasive blasting is performed on substrates, such as concrete, that contain crystalline silica.

Employer Requirements

The RCS standard requires employers to limit exposures to respirable crystalline silica and to take other steps to protect workers. It also provides flexible alternatives, especially useful for small employers (those with fewer than 250 workers on site, and fewer than 500 companywide). Employers can use a control method as shown in the Standard, or they can measure workers’ exposure to silica and independently decide which dust control methods work best to limit exposures to the permissible exposure limit (PEL) in their workplaces. Regardless of which exposure control method is used, all construction employers covered by the Standard are required to adhere to all requirements, including:

Establish and implement a written exposure control plan that identifies tasks that involve exposure and methods used to protect workers, including procedures to restrict access to work areas where high exposures may occur
Designate a competent person to implement the written exposure control plan
Restrict housekeeping practices that expose workers to silica where feasible alternatives are available
Provide respiratory protection when required
Offer medical exams—including chest X-rays and lung function tests—every three years for workers who are required by the Standard to wear a respirator for 30 or more days per year
Keep records of medical examinations
Communicate hazards and train employees

Employers must also comply with OSHA’s Hazard Communication Standard (HCS) (29 CFR 1910.1200). HCS requires employers to inform employees about hazardous chemicals in the workplace, such as respirable crystalline silica, through their written hazard communication programs. Written hazard communication programs must describe how requirements for container labels, safety data sheets (SDSs), and employee training will be met. As part of their hazard communication program for respirable crystalline silica, employers must address at least these health hazards: cancer, immune system, kidney, and lungs. Under the HCS, employers must:

Inform employees about the general requirements of HCS, as well as where and how they can view the written hazard communication program, lists of hazardous chemicals, and SDSs.
Train employees on how the presence or release of hazardous chemicals in the work area is detected; in the case of respirable crystalline silica, this could include methods the employer uses to measure exposures, such as air sampling or objective data. If employers are using Table 1 in the Standard (see below), they can train employees to recognize that an increase in visible dust is a sign that a control method may not be working properly.
Train employees on the details of the workplace-specific hazard communication program developed by the employer, such as container labels, the workplace labeling system, SDSs (including the order in which the information is presented), and how employees can get and use hazard information.

Methods of Compliance with Silica Standard

Employers following alternative exposure control methods must comply with the Standard's requirements, which requires employers to protect employees following the hierarchy of controls, a long-standing OSHA policy. This hierarchy relies on engineering and work practice controls for reducing exposures and allows for respirator use, in addition to those controls, only when feasible engineering controls cannot reduce exposures to acceptable levels.

Engineering and Work Practice Controls

Employers must use engineering and work practice controls to reduce and keep employee exposure to respirable crystalline silica at or below the permissible exposure limit (PEL) of 50 μg/m3 (50 micrograms per cubic meter) of air unless the employer can demonstrate that such controls are not feasible. The previous PEL was 100 μg/m3. If feasible engineering and work practice controls are not able to reduce employee exposures to or below the PEL, employers must still use feasible controls to reduce exposures to the lowest possible level and then use respiratory protection along with those controls.

Engineering Controls

The main types of engineering controls for silica are wet suppression methods and local exhaust ventilation. Wet suppression methods involve applying water or foam at the point of dust generation to keep dust from getting into the air. An example is an integrated water delivery system on a handheld pneumatic jackhammer/breaker.

Wet Method/Water Delivery Systems

Integrated water delivery systems are required for several types of equipment in the table below (Table 1 of the Standard). Integrated water systems must be developed specifically for the type of tool in use so they will apply the appropriate amount and flow rate of water at the appropriate dust emission points based on tool configuration, and do not interfere with other tool components or safety devices.

The appropriate water flow rates for controlling silica dust emissions can vary. The water must be applied at flow rates sufficient to minimize release of visible dust. Effective control of the dust depends on factors such as dust particle size, dust particle velocity, spray nozzle size and location, use of surfactants or other binders, and environmental factors (water hardness, humidity, weather, etc.), all of which must be considered when using wet methods.

Any slurry generated when using water to suppress dust should be cleaned up to limit secondary exposure to silica dust when the slurry dries. Follow procedures described in the employer’s Written Exposure Control Plan. When working in cold temperatures, where there is a risk of water freezing, additional work practices such as insulating drums, wrapping drums with gutter heat tape or adding environmentally-friendly antifreeze additives to water may be needed.

Local Exhaust Ventilation and Isolation

Local exhaust ventilation removes dust by capturing it at or near the point where it is created. An example is a dust collector for a handheld grinder. Another engineering control is isolation. Isolation separates employees from the dust source by containing the dust or isolating employees. An example is a properly ventilated cab on heavy equipment.

Advantages of engineering controls include:

Control of crystalline dust particles containing silica at the source, thus minimizing exposures to all persons in the surrounding work area
Reliable, predictable, and consistent levels of protection to a large number of employees
Can be monitored
Less prone to human error than the use of personal protective equipment

Work Practice Controls

Work practice controls involve performing a task in a way that reduces the likelihood or levels of exposure. Work practice controls are often used with engineering controls to protect employees. Employees must know the appropriate work practices for maximizing the effectiveness of controls and minimizing exposures. Examples of work practice controls include:

Inspecting and maintaining controls to prevent or fix malfunctions that would result in increased exposures
Making sure that nozzles spray water at the point of dust generation for wet method controls
Making sure that hoses are not kinked, or do not impede a tool used with a dust collector
Wetting down silica dust before sweeping it up
Scheduling work so that tasks that involve high exposures are performed when no other employees are in the area Under the hierarchy of controls, respirators can be another effective way to protect employees. However, respirators may be less practical or effective than engineering controls for the following reasons:
- Respirators must be selected for each worker, fitted, occasionally refitted, and regularly maintained (including replacing filters and other parts as necessary)
- Employees have to consistently and correctly use properly fitted respirators but may resist wearing them because respirators can be uncomfortable, especially in hot weather
- Respirators may put a physical strain on employees’ bodies, as a result of the respirator’s weight and because they increase breathing resistance. Employees with some health conditions cannot wear respirators because the physical strain of wearing the respirator increases their risk of illness, injury, and even death
- Respirators can create safety concerns because they interfere with workers’ ability to hear, see, smell and communicate
- Respirators protect only the employees wearing them

Table 1 in the Standard (shown below) matches common construction tasks with dust control methods, so employers know exactly what they need to do to limit worker exposure to silica. The dust control measures listed in the table include methods known to be effective, like using water to keep dust from getting into the air or using ventilation to capture dust. In some operations, respirators may also be needed. Employers who follow Table 1 correctly are not required to measure workers’ exposure to silica and are not subject to the PEL.

Equipment/Task	Engineering & Work Practice Control Methods	Required Respiratory Protection & Minimum Assigned Protection Factor (APF)
Equipment/Task	Engineering & Work Practice Control Methods	≤ 4 Hours /shift	> 4 Hours /shift
(i) Stationary masonry saws	Use saw equipped with an integrated water delivery system that continuously feeds water to the blade. Operate and maintain tools in accordance with manufacturer's instructions to minimize dust emissions.	None	None
(ii) Handheld power saws (any blade diameter)	Use saw equipped with an integrated water delivery system that continuously feeds water to the blade. Operate and maintain tools in accordance with manufacturer's instructions to minimize dust emissions.	Outdoors: None Indoors/enclosed area: APF 10	Outdoors: APF 10 Indoors/enclosed area: APF 10
(iii) Handheld power saws for cutting fiber-cement board (with blade diameter of 8 inches or less)	For tasks performed outdoors only: Use saw equipped with a commercially available dust collection system. Operate and maintain tools in accordance with manufacturer's instructions to minimize dust emissions. Dust collector must provide the air flow recommended by the tool manufacturer, or greater, and have a filter with 99% or greater efficiency.	None	None
(iv) Walk-behind saws	Use saw equipped with an integrated water delivery system that continuously feeds water to the blade. Operate and maintain tools in accordance with manufacturer's instructions to minimize dust emissions.	Outdoors: None Indoors/enclosed area: APF 10	Outdoors: None Indoors/enclosed area: APF 10
(v) Driveable saws	For tasks performed outdoors only: Use saw equipped with an integrated water delivery system that continuously feeds water to the blade. Operate and maintain tools in accordance with manufacturer's instructions to minimize dust emissions.	None	None
(vi) Rig-mounted core saws and drills	Use tool equipped with integrated water delivery system that supplies water to cutting surface. Operate and maintain tools in accordance with manufacturer's instructions to minimize dust emissions.	None	None
(vii) Handheld or stand-mounted drills (including impact and rotary hammer drills)	Use drills equipped with a commercially available shroud or cowling with the dust collection system. Operate and maintain tools in accordance with manufacturer's instructions to minimize dust emissions. Dust collector must provide the air flow recommended by the tool manufacturer, or greater, and have a filter with 99% or greater efficiency and a filter-cleaning mechanism. Use a HEPA-filtered vacuum when cleaning holes.	None	None
(viii) Dowel drilling rigs for concrete	For tasks performed outdoors only: Use shroud around drill bits with a dust collection system. Dust collectors must have a filter with 99% or greater efficiency and a filter-cleaning mechanism. Use a HEPA-filtered vacuum when cleaning holes.	APF 10	APF 10
(ix) Vehicle-mounted drilling rigs for rock and concrete	Use a dust collection system with a close capture hood or shroud around drill bits with a low-flow water spray to wet the dust at the discharge point from the dust collector. OR Operate from within an enclosed cab and use water for dust suppression.	None	None
(x) Jackhammers & handheld powered chipping tools	Use tools with a water delivery system that supplies a continuous stream or spray of water at the point of impact. - When used outdoors. - When used indoors or in an enclosed area. OR Use tool equipped with a commercially available shroud and dust collection system Operate and maintain tools in accordance with manufacturer's instructions to minimize dust emissions. Dust collector must provide the airflow recommended by the tool manufacturer, or greater, and have a filler with 99% or greater efficiency and a filter-cleaning mechanism.	Outdoors: None Indoors/enclosed area: APF 10	Outdoors: APF 10 Indoors/enclosed area: APF 10
(xi) Handheld grinders for mortar removal (i.e., tuckpointing)	Use grinders equipped with a commercially available shroud and dust collection system. Operate and maintain tools in accordance with manufacturer's instructions to minimize dust emissions. Dust collectors must provide 25 cubic feet per minute (cfm) or greater of airflow per inch of wheel diameter and have a filter with 99% or greater efficiency and a cyclonic pre-separator or filter-cleaning mechanism.	APF 10	APF 25
(xii) Handheld grinders for uses other than mortar removal	For tasks performed outdoors only: Use grinders equipped with an integrated water delivery system that continuously feeds water to the grinding surface. Operate and maintain tools in accordance with manufacturer's instructions to minimize dust emissions. OR Use grinders equipped with a commercially available shroud and dust collection system. Operate and maintain tools in accordance with manufacturer's instructions to minimize dust emissions. Dust collectors must provide 25 cubic feet per minute (cfm) or greater of airflow per inch of wheel diameter and have a filter with 99% or greater efficiency and a cyclonic pre-separator or filter-cleaning mechanism.	None	None OR Outdoors: None Indoors/enclosed area: APF 10
(xiii) Walk-behind milling machines and floor grinders.	Use machines equipped with an integrated water delivery system that continuously feeds water to the cutting surface. Operate and maintain tools in accordance with manufacturer's instructions to minimize dust emissions. OR Use machines equipped with a dust collection system recommended by the manufacturer. Operate and maintain tools in accordance with manufacturer's instructions to minimize dust emissions. Dust collector must provide the air flow recommended by the manufacturer, or greater, and have a filter with 99% or greater efficiency and a filter-cleaning mechanism. When used indoors or in an enclosed area, use a HEPA-filtered vacuum to remove loose dust in between passes.	None	None
(xiv) Small drivable milling machines (less than half-lane)	Use a machine equipped with supplemental water sprays designed to suppress dust. Water must be combined with a surfactant. Operate and maintain machines to minimize dust emissions.	None	None
(xv) Large drivable milling machines (half-lane and larger)	For cuts of any depth on asphalt only: Use machine equipped with exhaust ventilation on drum enclosure and supplemental water sprays designed to suppress dust. Operate and maintain machines to minimize dust emissions. For cuts of four inches in depth or less on any substrate: Use machine equipped with exhaust ventilation on drum enclosure and supplemental water sprays designed to suppress dust. Operate and maintain machines to minimize dust emissions. OR Use a machine equipped with supplemental water spray designed to suppress dust. Water must be combined with a surfactant. Operate and maintain machines to minimize dust emissions.	None	None
(xvi) Crushing machines	Use equipment designed to deliver water spray or mist for dust suppression at crusher and other points where dust is generated (e.g., hoppers, conveyors, sieves/sizing or vibrating components, and discharge points). Operate and maintain machines in accordance with manufacturer's instructions to minimize dust emissions. Use a ventilated booth that provides fresh, climate-controlled air to the operator, or a remote control station.	None	None
(xvii) Heavy equipment and utility vehicles used to abrade or fracture silica-containing materials or used during demolition involving silica-containing materials	Operate equipment from within an enclosed cab. When employees outside of the cab are engaged in the task, apply water and/or dust suppressants as necessary to minimize dust emissions.	None	None
(xviii) Heavy equipment and utility vehicles for tasks such as grading and excavating but not including: demolishing, abrading, or fracturing materials containing silica	Apply water and/or dust suppressants as necessary to minimize dust emissions. OR When the equipment operator is the only employee engaged in the task, operate equipment from within an enclosed cab.	None	None

Specified exposure control methods.
(1) For each employee engaged in a task identified in Table 1, the employer shall fully and properly implement the engineering controls, work practices, and respiratory protection specified for the task in Table 1, unless the employer assesses and limits the exposure of the employee to respirable crystalline silica in accordance with paragraph (d) of this section.
(2) When implementing the control measures specified in Table 1, each employer shall:
(i) For tasks performed indoors or in enclosed areas, provide a means of exhaust as needed to minimize the accumulation of visible airborne dust;
(ii) For tasks performed using wet methods, apply water at flow rates sufficient to minimize the release of visible dust;
(iii) For measures implemented that include an enclosed cab or booth, ensure that the enclosed cab or booth:
(a) Is maintained as free as practicable from settled dust;
(b) Has door seals and closing mechanisms that work properly;
(c) Has gaskets and seals that are in good condition and working properly;
(d) Is under positive pressure maintained through continuous delivery of fresh air;
(e) Has intake air that is filtered through a filter that is 95% efficient in the 0.3-10.0 μm range (e.g., MERV-16 or better); and
(f) Has heating and cooling capabilities.
(3) Where an employee performs more than one task on Table 1 during the course of a shift, and the total duration of all tasks combined is more than four hours, the required respiratory protection for each task is the respiratory protection specified for more than four hours per shift. If the total duration of all tasks in Table 1 combined is less than four hours, the required respiratory protection for each task is the respiratory protection specified for less than four hours per shift.

Retrofit Your Pneumatic Jackhammer to Comply with OSHA's RCS Standard

In response to OSHA's new standard, Parker developed the 7084 Series Twinhammer hose and a conversion kit to convert virtually any jackhammer to a tool compliant with RCS rules.

Adapting existing equipment to combine air and water lines typically requires clamps or straps that can loosen or snag, becoming potential safety hazards that must be routinely inspected and reapplied. Bonded twin-line hose solutions like Parker’s Twinhammer hose help companies meet OSHA standards while creating a safer and more efficient work environment.

Parker's jackhammer conversion kit includes the hardware and attachment components to install Parker Twinhammer hose onto many models and generations of traditional jackhammers. Each kit contains the straps, shims, connectors, valves, and nozzles necessary to attach the hose to existing equipment. Adding the capability to spray water on work surfaces during operation will help to suppress any airborne particles that are created when the jackhammer tip breaks rock, concrete, and other materials containing crystalline silica.

Click here to download detailed instructions (with images of each step) on how to retrofit your jackhammer with the Twinhammer conversion kit.

For more information about compliance and exposure requirements, visit OSHA's website for their RCS Standard, which provides detailed information, fact sheets and links to relevant documentation. You can also find a PDF of the complete text of the regulation: §1926.1153 Respirable crystalline silica.