Construction Industry silica hazards

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## § 1532.3. Occupational Exposures to Respirable Crystalline Silica. (cont.) (2) When implementing the control measures specified in Table 1, each employer shall: (A) For tasks performed indoors or in enclosed areas, provide a means of exhaust as needed to minimize the accumulation of visible airborne dust; (B) For tasks performed using wet methods, apply water at flow rates sufficient to minimize release of visible dust; (C) For measures implemented that include an enclosed cab or booth, ensure that the enclosed cab or booth: 1. Is maintained as free as practicable from settled dust; 2. Has door seals and closing mechanisms that work properly; 3. Has gaskets and seals that are in good condition and working properly; 4. Is under positive pressure maintained through continuous delivery of fresh air; 5. 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 6. 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 on 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. (d) Alternative exposure control methods. For tasks not listed in Table 1, or where the employer does not fully and properly implement the engineering controls, work practices, and respiratory protection described in Table 1: (1) Permissible exposure limit (PEL). The employer shall ensure that no employee is exposed to an airborne concentration of respirable crystalline silica in excess of 50 µg/m 3 calculated as an 8-hour TWA. (2) Exposure assessment. (A) General. The employer shall assess the…

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# Engineered Stone Countertop Fabrication (cont.) ## How to prevent overexposures to workers? The best way is keep the dust out of the air by using: • Water when cutting, grinding, and shaping, whenever possible. • Local exhaust ventilation at the source generating the airborne dust. The types of controls used for cutting or grinding natural stone countertops can usually be effectively used for engineered stone. No matter which controls are used, it is very important that they be properly: • Designed, as most homemade or aftermarket controls do not work as well as those designed by the manufacturer of the machine. - Maintained. - Used according to the manufacturer instructions, including using the required amounts of exhaust ventilation or water. ## Respirators should only be used: - As a last resort for protection when local exhaust ventilation or water controls are not feasible or do not adequately control employee airborne exposures. - Where exposures exceed the permissible exposure limit (50 µg/m3, 8-hour TWA) while installing or implementing feasible engineering and work practice controls. • When the employee is in a regulated area. Housekeeping methods such as dry sweeping and using compressed air can result in high dust exposures and must be avoided, where feasible. Use water or a properly filtered vacuum. ## What are the Cal/OSHA regulatory requirements? Respirable Crystalline Silica Standards - Important Update outlines the relevant Title 8, California Code of Regulations requirements: • 5204: Countertop manufacturing • 1532.3: Construction • 5155: Permissible Exposure Levels Besides silica, a number of other hazards may be present in an engineered stone countertop fabrication workplace, including: • Other hazardous materials, such as granite, resins, solvents, and coatings. • Machine and electrical hazards. • Noise. • Back and other musculoskeletal injuries from lifting heavy countertops. • Crushing hazards from working arou…

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## § 1532.3. Occupational Exposures to Respirable Crystalline Silica. (cont.) 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. Specialist means an American Board Certified Specialist in Pulmonary Disease or an American Board Certified Specialist in Occupational Medicine. This Section means this respirable crystalline silica standard, Section 1532.3. (c) Specified exposure control methods. (1) For each employee engaged in a task identified on Table 1, the employer shall fully and properly implement the engineering controls, work practices, and respiratory protection specified for the task on Table 1, unless the employer assesses and limits the exposure of the employee to respirable crystalline silica in accordance with subsection (d). Table 1 - Specified Exposure Control Methods When Working With Materials Containing Crystalline Silica <table><tr><th></th><th></th><th colspan="2">Required respiratory</th></tr><tr><td></td><td></td><td colspan="2">protection and mimimum</td></tr><tr><td></td><td></td><td colspan="2">assigned protection factor</td></tr><tr><td>Equipment/task</td><td>Engineering and work practice control methods</td><td>(APF)</td><td></td></tr><tr><td></td><td></td><td>≤ 4 hours/shift</td><td>&gt; 4 hours/shift</td></tr><tr><td></td><td></td><td></td><td></td></tr><tr><td>(i) Stationary masonry saws</td><td>Use saw equipped with integrated water delivery system that</td><td>None</td><td>None.</td></tr><tr><td></td><td>continuously feeds water to the blade</td><td></td><td></td></tr><tr><td></td><td>Operate and maintain tool in accordance with manufacturer's</td><td></td><td></td></tr><tr><td><…

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# Illustration 10 | Hitches for Holding Needle Beams (cont.) (8) Horse scaffolds. 1647 - The specifications for horse scaffolds are as follows: - Platform width: i. Light trades = 20 inches (min.); 10 inches if the platform is less than 4 ft.high. ii. Heavy trades = 4 ft. (min.). 1647(e)(2) iii. Width of base legs = 1/2 x height (min.). 1647(a)(3) . Height: i. Collapsible horse = 6 ft. (max.). 1647(d)(2) ii. Single horse = 10 ft. (max.). 1647(e)(1) iii. Two tiers (max.) = 10 ft. (max.). 1647(e)(1) (9) Ladder jack scaffolds. 1648 - The specifications for ladder jack scaffold platforms are as follows: • Span 16 ft. (max.) 1648(b) . Height 16 ft. (max.) 1648(a) • Width 14 in. (min.) 1648(b) - Load = two workers (max.) 1648(a) - Notes: >>Ladders must be Type I, IA, or IAA duty rated ladders in accordance with 3276(c). Job-built ladders shall not be used for this purpose. 1648(d) >> A safety line is required for each worker. 1648(c) (10) Window jack scaffolds. 1654 - The specifications for window jack scaffolds are as follows: • Only one window per scaffold is permitted. 1654(d) - The load limit is one person per scaffold. 1654(d) . Fall protection or railings are required. 1654(c) # Silica Dust Construction work that involves exposure to crystalline silica- containing materials can cause lung diseases. These silica- containing materials include (but are not limited to): - Sand - Rock • Ceramic and terracotta tiles - Concrete and concrete block - Manufactured stone - Roof tiles - Bricks and blocks • - Grouts and mortar • Some joint compounds • Abrasive materials Exposure to crystalline silica can cause a variety of lung diseases, including silicosis, lung cancer, COPD (chronic obstructive pulmonary disease), decreased lung function, increased likelihood of getting tuberculosis, and immune system and kidney effects. Although most cases of silicosis develop after years of exposure, instances of extremely hig…

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# Emergency Temporary Silica Standard What Employers Need to Know (cont.) ## Written exposure control plan Expand the written exposure control plan to include: • Air monitoring records showing that engineering controls reduce employee exposure to airborne respirable silica to less than the action level. • Procedures for the proper use of personal protective equipment. • Documentation of proper report of carcinogen use to Cal/OSHA as required by section 5203. • Training procedures to ensure employees can prevent RCS exposures. ## Employee communication and training Ensure that employees understand the following: • How to use the required dust control methods, including work practices and respiratory protection to prevent dust exposures. • The health hazards and symptoms of excessive RCS airborne exposures, such as cough, difficulty breathing, fatigue, shortness of breath, weakness, fever, chest pain, or unexpected weight loss - including how crystalline silica dust can worsen the effects of smoking and tuberculosis. • They are encouraged to seek medical attention if they think they are experiencing RCS airborne exposure- related symptoms. Early diagnosis and treatment is important. ## Respirator protection 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 must be provided for mandatory employee use. Combination organic vapor cartridges must also be used for artificial stone unless the employer demonstrates that employee exposures to any organic compounds known to be present in the artificial stone are not above the corresponding permissible exposure levels established in section 5155. Loose-fitting PAPR, non-powered full-facepiece air-purifying respirator, or an equally protective alternative, such as a half-face PAPR may be permitted if an employer demonstrates exposures are below the action level through air monitoring every six mont…

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# HAZARD ALERT State of California CAL OSHA Department of Industrial Relation ## To: Employees and employers in the granite counter top fabrication industry Fabricating granite counter tops and other silica-containing materials may expose workers to levels of respirable crystalline silica above state limits, as was found recently by the California Division of Occupational Safety and Health. Workers who inhale excessive amounts of crystalline silica can develop silicosis, a serious and potentially fatal lung disease. Silicosis is a progressive and irreversible condition of the lung that can lead to serious disability or death. Additionally, the International Agency for Research on Cancer (IARC) considers inhaled crystalline silica to be a known human carcinogen. Crystalline silica is a natural component of the earth's crust and is a basic component of sand, quartz, and granite rock. Workers with impaired lung function due to silica exposure are more susceptible to other respiratory diseases such as tuberculosis. The health hazards of silica are not new. Silicosis is one of the world's oldest known occupational diseases, with reports dating back to ancient Greece. Although very high short-term exposures to silica (as experienced by many workers in past times) can pose a serious health hazard, long-term exposures to silica levels exceeding the state limits also pose serious health hazards. Activities such as grinding, cutting, routing, drilling, chipping, or polishing on granite and other stone materials containing crystalline silica can create airborne dust and the potential for a health hazard to workers. The granite itself or the finished counter top does not present a health hazard. Silica exposures above the permissible exposure limit were found during recent inspections by the California Division of Occupational Safety and Health at granite counter top fabrication facilities. High silica exposures have also been found in other businesses performing simila…

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# Crystalline Silica Content of Materials (cont.) ## What Must Your Employer do to Protect Workers? (cont.) - Use engineering controls and safe work practices to maintain employee exposures below the PEL. • Engineering controls that an employer can use include: - о Substitution. Use a material that has a low silica content, such as marble or limestone, instead of artificial stone. - о Isolation. Use automated machines in enclosed areas separated from workers. ○ Barriers. Use physical barriers or partitions to separate cutting, grinding, or polishing areas from other parts of the workplace to prevent the spread of silica dust. - о Wet methods (required at all times for high-exposure trigger tasks). Ensure water covers the entire surface of the stone slab where a tool, piece of equipment, or machine contacts the stone. Water that is recycled must be filtered to remove silica. Use one or a combination of the following wet methods: ◆ Sheet-wetting, which forms a continuous flow of water over the surface of the work object. ◆ Tools with built-in water application systems, such as saws, grinders, chippers and polishers. - Water-jet cutters. ◆ Wet milling machines and wet stone routers. - Automated machines with built-in water application. - о Ventilation. Use local exhaust ventilation to remove silica dust from the air at the point where the tool or equipment contacts the stone and before the dust enters the worker's breathing zone. Exhausted air must go through a HEPA filter to remove respirable crystalline silica. - Safe work practices include: ■ Training employees to perform tasks and use tools, water systems, and ventilation in a way that prevents dust exposures. ■ Scheduling work so that high-exposure tasks are performed when fewer or no other employees are in the regulated area. - Cleaning work areas frequently using wet methods or HEPA-filtered vacuums to prevent re-suspension of silica dust. ■ Ensuring that emp…

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## § 1532.3. Occupational Exposures to Respirable Crystalline Silica. (cont.) nonetheless use them to reduce employee exposure to the lowest feasible level and shall supplement them with the use of respiratory protection that complies with the requirements of subsection (e). (B) Abrasive blasting. In addition to the requirements of subsection (d)(3)(A), the employer shall comply with other Title 8 standards, when applicable, such as section 1530 (Ventilation), where abrasive blasting is conducted using crystalline silica-containing blasting agents, or where abrasive blasting is conducted on substrates that contain crystalline silica. (e) Respiratory protection. (1) General. Where respiratory protection is required by this section, the employer must provide each employee an appropriate respirator that complies with the requirements of this subsection and Section 5144. Respiratory protection is required: (A) Where specified by Table 1 of subsection (c); or (B) For tasks not listed in Table 1, or where the employer does not fully and properly implement the engineering controls, work practices, and respiratory protection described in Table 1: 1. Where exposures exceed the PEL during periods necessary to install or implement feasible engineering and work practice controls; 2. Where exposures exceed the PEL during tasks, such as certain maintenance and repair tasks, for which engineering and work practice controls are not feasible; and 3. During tasks for which an employer has implemented all feasible engineering and work practice controls and such controls are not sufficient to reduce exposures to or below the PEL. (2) Respiratory protection program. Where respirator use is required by this section, the employer shall institute a respiratory protection program in accordance with Section 5144. (3) Specified exposure control methods. For the tasks listed in Table 1 in subsection (c), if the employer fully and properly implements the engineering controls…

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# § 5204. Occupational Exposures to Respirable Crystalline Silica. (cont.) 3. Use of employee rotation as a means of reducing employee exposure to respirable crystalline silica. 4. Walking or moving equipment on or through dry dust, debris, residue, or other materials that may contain crystalline silica. (3) Written exposure control plan. (A) The employer shall establish and implement a written exposure control plan that contains at least the following elements: 1. A description of the tasks in the workplace that involve exposure to respirable crystalline silica; 2. A description of the engineering controls, work practices, and respiratory protection used to limit employee exposure to respirable crystalline silica for each task; and 3. A description of the housekeeping measures used to limit employee exposure to respirable crystalline silica. (B) The employer shall review and evaluate the effectiveness of the written exposure control plan at least annually and update it as necessary. (C) The employer shall make the written exposure control plan readily available for examination and copying, upon request, to each employee covered by this section, their designated representatives, the Chief, and the Director. (D) In addition to the requirements of subsections (f)(3)(A) through (f)(3)(C), workplaces where high-exposure trigger tasks occur shall also include the following in their written exposure control plan: 1. Results of air monitoring conducted by a qualified person demonstrating whether engineering controls are effective at continuously maintaining exposure levels below the action level. 2. Procedures for the proper donning and doffing of personal protective equipment, including work clothing and respiratory protection, to effectively prevent exposures to respirable crystalline silica above the actin level and prevent take-home exposures. 3. Documentation of proper reporting to the Division, pursuant to Section 5203, (Carcinogen Report of U…

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## § 1532.3. Occupational Exposures to Respirable Crystalline Silica. (cont.) meet this requirement. In representative sampling, the employer shall sample the employee(s) who are expected to have the highest exposure to respirable crystalline silica. 2. If initial monitoring indicates that employee exposures are below the action level, the employer may discontinue monitoring for those employees whose exposures are represented by such monitoring. 3. Where the most recent exposure monitoring indicates that employee exposures are at or above the action level but at or below the PEL, the employer shall repeat such monitoring within six months of the most recent monitoring. 4. Where the most recent exposure monitoring indicates that employee exposures are above the PEL, the employer shall repeat such monitoring within three months of the most recent monitoring. 5. Where the most recent (non-initial) exposure monitoring indicates that employee exposures are below the action level, the employer shall repeat such monitoring within six months of the most recent monitoring until two consecutive measurements, taken seven or more days apart, are below the action level, at which time the employer may discontinue monitoring for those employees whose exposures are represented by such monitoring, except as otherwise provided in subsection (d)(2)(D). (D) Reassessment of exposures. The employer shall reassess exposures whenever a change in the production, process, control equipment, personnel, or work practices may reasonably be expected to result in new or additional exposures at or above the action level, or when the employer has any reason to believe that new or additional exposures at or above the action level have occurred. (E) Methods of sample analysis. The employer shall ensure that all samples taken to satisfy the monitoring requirements of subsection (d)(2) are evaluated by a laboratory that analyzes air samples for respirable crystalline silica in accordance with …