In the battle against dust on the jobsite, the enemy is silica—airborne crystalline silica dust, that is. It’s found in abundance in sand and rock, so it’s everywhere on most concrete jobsites.
OSHA has proposed rules to limit exposure. The ruling has yet to become an OSHA mandate, but the proposals have been bouncing among stakeholders for years now. Most industry experts say it’s only a matter of time before an exposure limit will pass. The proposed limit for worker exposure currently stands at 25 micrograms per cubic meter of air averaged over an eight-hour day.
If the limit’s implemented, OSHA could require any worker cutting into concrete, stone, masonry, and ceramics to employ a host of engineering controls. These center on the use of wet saws, vacuum dust collection, work-site isolation strategies, and personal protective equipment. An N95 NIOSH-certified respirator, such as the one shown in the photo above, will likely become mandatory for every worker on any job requiring concrete mixing, jack hammering, rock drilling, concrete and masonry drilling, and sawing.
As with European Union vibration standards (see “Decreasing Tool Vibration,” page 6), the EU is ahead of the curve. It has already mandated strict controls on silica dust, and toolmakers selling in EU markets have ready-made solutions, which—not surprisingly given OSHA’s attention—are increasingly showing up in the U.S. power-tool market. These solutions include dust-containment shrouds with vacuum attachments for drills and rotary hammers and for dry-cut concrete saws. Integral are jobsite vacuums with self-cleaning filters optimized for picking up fine dust.
Whether or not the OSHA rule passes, there is a secondhand benefit to sharing a market full of tools and equipment born under more stringent dust-control standards: We enjoy a cleaner jobsite and breathe less dust, and that affords a level of convenience and efficiency that helps productivity. Wouldn’t you rather clear dust from a drilled fastener hole with a vacuum than use a rubber bellows or compressed air, letting all that dust blow up in your face?