Environmental Health & Safety

Occupational Safety Unit

Silica Exposure Control Plan

Crystalline silica is a natural material found abundantly in the earth's crust. Other common names for crystalline silica are silicon dioxide, quartz, cristobalite, and tridymite. Quartz, the most common form of silica, is a component of sand, stone, rock, concrete, brick, ceramic tiles, block, and mortar. Silica dust may be hazardous when very small (respirable) particles are inhaled. These respirable dust particles can penetrate deep into the lungs and after many years of exposure may cause disabling and sometimes fatal lung diseases, including silicosis and lung cancer. Silica presents a hazard when respirable dust is created and inhaled. Work tasks that can generate silica dust include cutting, sawing, drilling, and crushing of concrete, brick, ceramic tiles, rock, and stone products.

OSHA has issued two standards to protect workers from exposure to respirable crystalline silica; one is for construction (Silica Construction Standard) and one for general industry (Silica General Industry Standard). The standards require employers to limit worker exposure to silica dust to less than 50 µg/m³, as an 8 hour time-weighted average. The OSHA Silica Standard allows the use of control methods listed in Table 1 of the OSHA Construction Standard in lieu of exposure monitoring.

Description of Tasks, Engineering Controls and Required Respiratory Protection:

The University of Rochester employs masons in the Medical Center Facilities Organization (MCFO). The masons routinely perform construction type work such as using masonry saws, grinders, drills and handheld chipping tools, which may expose them to respirable silica dust.

In addition, Central Utilities, MCFO, River Campus Facilities, and LLE have employees that may perform tasks that may expose them to silica dust including some listed in Table 1 of the OSHA Construction Standard. Major construction/renovation jobs involving potential silica exposure are done by contractors. UR Project Managers must ask contractors for a copy of their Silica Exposure Control Plan and review it before starting a project that may involve silica dust to ensure proper dust control methods will be used. Each organization that performs tasks listed in Table 1 must identify a Designated Competent Person to make frequent and regular inspections of job sites and equipment to ensure the proper dust control methods are implemented.

UR employees should use the dust control methods specified in Table 1 of the Silica Standard, unless a process review is done with Environmental Heatlh & Safety (EH&S) prior to the job. Table A below lists the tasks done at UR and the specific control method in place. A respirator with APF (Assigned Protection Factor) 10 can be either a N95 dust mask or a half-face cartridge respirator. A PAPR (Powered-Air Purifying Respirator) has an APF equal to 25. If a task is not listed on Table A that may expose UR employees to silica dust, contact EH&S for a review and determination of possible exposure monitoring needs.

Housekeeping:

HEPA (High Efficiency Particulate Air) filter vacuum or wet cleaning methods shall be used for cleanup if silica dust may be present. Dry sweeping or use of compressed air can NOT be used for cleaning purposes.

Restricted Work Areas:

Any indoor work site with potential exposure to silica dust will have restricted access with floor to ceiling partitions (i.e. plastic or hard wall portable system). Return ventilation grids will be blocked off and the area will be setup to be negative pressure to adjacent areas.  Outdoor work sites will have construction fences/cones to restrict access.

Training:

Silica Training is required for all employees who may perform tasks which may expose them to silica dust, including tasks listed in Table A of this document. The EH&S Silica Training module is available on MyPath, or EH&S may be contacted to schedule in-person training. Training must be given on initial hire and annually thereafter.

Medical Surveillance:

Must be offered to employees who are required to wear a respirator for 30 or more days a year to minimize exposure to silica. Masons working full time at the UofR may qualify for medical surveillance.

Table A: Tasks done at UR and the respective controls in place

Equipment/Task	Control Method	Required Respirator if ≤ 4 hours per shift	Required Respirator if > 4 hours per shift
Stationary masonry saws	Integrated Water Delivery System	None	None
Handheld power saws	Integrated Water Delivery System -when used outdoors -when used indoors or enclosed area	None APF 10	APF 10 APF 10
Rig-mounted core saws or drills	Integrated water delivery system	None	None
Handheld and stand-mounted drills	Shroud with dust collection system	None	None
Dowel drilling rigs for concrete	Shroud with dust collection system. Use HEPA vacuum for cleaning holes.	APF 10	APF 10
Jackhammer and handheld chipping tools	Shroud and dust collection system -when used outdoors -when used indoors or enclosed area	None APF 10	APF 10 APF 10
Handheld grinders for mortar removal	Shroud with dust collection system (min 25 cfm per inch of wheel diameter)	APF 10	APF 25
Handheld grinders for uses other than mortar removal	Integrated water delivery system OR shroud and dust collection system   -when used outdoors   -when used indoors or in enclosed area	None None None	None None APF 10
Demolition of block wall with sledge hammer*	Wet methods	APF 10	APF 10

*Not listed in OSHA Table 1, may need exposure monitoring

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QUESTIONS or COMMENTS?
Contact EH&S at (585) 275-3241 or e-mail Questions.

This page last updated 12/2/2022. Disclaimer.