RESPIRABLE CRYSTALLINE SILICA

Please refer to the OSHA standards for all requirements found in 29 CFR 1910.1053 and 29 CFR 1926.1153. This presentation does not address all requirements of these standards. The building owner is often considered the statutory employer as per OSHA Regulations.

Effective Dates Construction Industry 6/23/2017 9/23/2017 just in case... General Industry and Maritime 6/23/2018 6/23/2021 for hydraulic fracturing engineering controls.

What is Silica? Silicon - The element Silicon (Si)

Silica Silicon dioxide - SiO2. Found in quartz, cristobalite and tridymite in a crystalline form.

Silicates Compounds containing silica, oxygen plus other elements. Cement, silicon carbide, garnet. Silicone Polysiloxanes – polymers. Found in rubber, caulks, etc.

Silicates and Silicone

What is Crystalline? Silica can occur in crystalline and amorphous states. Amorphous silica does not pose the same hazards as crystalline silica and is not addressed by this standard. E.G. glass, diatomaceous earth (uncalcined), precipitated silica, and silica gel Crystalline materials have a highly ordered structure – amorphous solids do not have an ordered structure.

Amorphous Glass Fiberglass Glazes Silica gel Mineral wool Slag abrasive blasting media Coal fly ash * Some diatomaceous earth products* Semiconductor products Fulgurite - lightning strike

Amorphous

What is Respirable? CEN1 Definition: The mass fraction of inhaled particles penetrating to the unciliated airways. i.e. can get into lower reaches of the lung. 1 European Committee for Standardization

OSHA Definition: 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.

Crystalline Amorphous Both are pure carbon

Presence of crystalline silica. What Is Exposure? Presence of crystalline silica. Presence of small respirable particles or activity that generates respirable particles. Respirable particles must become airborne.

Permissible Exposure Limit Action Level and Permissible Exposure Limit Action Level – 25µg/M3 PEL – 50µg/M3 Performance Option – Air sampling and objective data to determine exposure. Scheduled Monitoring.

Exposure Assessment Reporting Results of exposure monitoring must be provided to employees within 5 or 15 working days after completion of monitoring. Construction – 5 days General Industry – 15 days

Regulated Areas 1910.1053 Any work area where exposures can reasonably be expected to exceed the PEL shall be established as a Regulated Area. Area must be demarcated and signs must be posted at all entrances. Access to area must be limited to authorized people. Must provide respirators and ensure use in area

Methods of Compliance - Written Exposure Control Plan Plan must include: Description of tasks involving exposure to silica. Description of engineering controls, work practices and respiratory protection used to limit exposure to silica.

Written Exposure Control Plan Description of housekeeping measures to limit employee exposure to silica. Review plan at least annually and update if necessary. Plan must be made available to employees and OSHA. 1926 – Competent Person

Methods of Compliance - 1926.1153(c) Table 1 Follow all engineering controls, work practices and respiratory protection requirements in Table 1 to be considered in compliance with standard. No exposure assessment is required if all Table 1 requirements are followed.

Table 1

Wet methods – apply sufficient water to minimize release of dust. Table 1 Requirements Indoors – use ventilation to minimize accumulations of visible airborne dust. Wet methods – apply sufficient water to minimize release of dust.

Housekeeping No dry sweeping or brushing unless wet sweeping and HEPA vacuuming is not feasible. No compressed air cleaning where activity could contribute to employee exposure.

Medical Surveillance General Industry – required for employees exposed at or above Action Level for 30 days or more per year. Construction Industry – required for employees who are required to wear a respirator for 30 or more days per year.

Medical Surveillance Initial and periodic exams at least every three years or more frequently if recommended by physician. Each exam includes mandatory chest X-ray, TB test and pulmonary function test. Chest X-ray not at discretion of physician.

Medical Surveillance Pulmonary function test (PFT) must be administered by technician with current certificate from a NIOSH approved spirometry course. Employer must pay for additional specialist examinations recommended by the physician.

Respiratory Protection Compliance with 29 CFR 1910.134 (Respiratory Protection) is required. Minimum requirement is an air purifying respirator with an assigned protection factor of 10. Filtering facepiece (dust mask) is acceptable if, 1N-95 2Fit-tested 3Medical Surveillance 42 straps 5NIOSH approved

Hazard Communication Employee training on the following is mandatory: Health hazards associated with silica exposure. Specific tasks that can result in exposure to silica.

Specific measures taken to protect employees from exposure to silica including engineering controls, work practices and respirators to be used. OSHA silica standard. Purpose and description of medical surveillance program.

Cyclones Particle impactors Sampling Methods Must collect respirable fraction of dust. Two major types of size-selective sampling devices: Cyclones Particle impactors

Cyclones Vortex separation - uses gravity and rotational effects to achieve particle separation.

Respirable particles exit to filter Air Inlet

Particle Impactors Larger (non-respirable) particles are separated by inertial impaction. Smaller respirable particles continue onward to collection media.

Large particles will be captured by impaction. Smaller particles go around to get collected on filter.

SKC PPI

SKC PPI Disposable $30 Lab $60 Reloadable $395

Dust Minimization Devices

Gypsum Wallboard and Compound Various manufacturers claim crystalline silica content ranging from <1% to 5% in gypsum board and joint compound products.

TTi Offers 34+ OSHA and EPA Training Courses Onsite Classes Available Dale J Becker Director, Environmental Safety & Health – Education Services C (602) 432-5319 dale.becker@mcconsultants.com 2122 W. Lone Cactus Dr. Suite 6, Phoenix, AZ 85027 T (760) 930-9966  F (760) 930-9974 www.mcconsultants.com