Saturday, November 11, 2023
Exposures to respirable crystalline silica occur when the following tools are used on concrete, brick, block, stone, mortar, and other materials that contain crystalline silica:
■ Stationary masonry saws.
■ Handheld power saws.
■ Walk-behind saws.
■ Drivable saws.
■ Rig-mounted core saws or drills.
■ Handheld and stand-mounted drills (including impact and rotary hammer drills).
■ Dowel drilling rigs.
■ Vehicle-mounted drilling rigs; ■ Jackhammers and handheld powered chipping tools.
■ Handheld grinders.
■ Walk-behind milling machines and floor grinders.
■ Drivable milling machines.
■ Crushing machines; and
■ Heavy equipment and utility vehicles when used to abrade or fracture silica containing materials (such as hoe ramming or rock ripping) or during demolition activities, and for tasks such as grading and excavating.
Although as electricians, we don't daily get exposed to silica dust, we do have to be observant of those time when we do. If we are drilling brick, concrete, or other masonry products, we should wet the surface where we are drilling with a spray bottle to limit the silica dust in the air, especially if we are drilling multiple holes.
Sometimes we have to do demolition activities of old foundations, or walls. We should always wear respirators when doing demolition operations of masonry products, especially with power tools such as saws and grinders.
If you need to do this type of work, let your supervisor know immediately about the additional hazard and we can make arrangements to do the work another way or ensure we have the proper protections in place.
Supervisors, ensure that you include silica exposure on your JHA every day if you are going to have the crew work with concrete, brick, or masonry products and include mitigations. If you are going to be doing more than drilling into concrete or masonry products, be sure to notify the Director of Education and Loss Prevention, so that your crew can be fit tested for respirators and respirators can be issued.
The key is the amount of work that will be done: If it is standard drilling of concrete and masonry, then no extra steps need to be taken.
The OSHA standard states this as: "Some employees in the construction sector perform tasks involving occasional, brief exposures to respirable crystalline silica that are incidental to their primary work. These workers include carpenters, plumbers, and electricians, who occasionally drill holes in concrete or masonry or perform other tasks that involve exposure to respirable crystalline silica. Where employees perform tasks that involve exposure to respirable crystalline silica for a very short period of time, exposures for many tasks will be below 25 μg/m3 as an 8-hour TWA. For example, for hole drillers using hand-held drills, if the duration of exposure is 15 minutes or less, the 8-hour TWA exposure can reasonably be anticipated to remain under the 25 μg/m3 threshold (assuming no exposure for the remainder of the shift)"
So… if you are unsure, call the Director of Education and Loss Prevention or the Regional Safety Manager for Advice on how to best proceed if you think you will be doing work that could result in more than the work describe here with silica containing materials.
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