Using a specially designed test bench,  the researchers have conducted experiments using a common hammer drill and carbide-tipped bit to isolate the effect of drill bit wear on worker exposure to these hazards.
CPWR Using a specially designed test bench, the researchers have conducted experiments using a common hammer drill and carbide-tipped bit to isolate the effect of drill bit wear on worker exposure to these hazards.

Workers who perform concrete drilling are exposed to hazardous levels of noise, force, vibration and airborne silica dust. Reducing the risks associated with those hazards is the focus of a study by David Rempel, a member of the Center for Construction Research and Training's research consortium, and his research team at the University of California.

Using a specially designed test bench (see photo) the researchers have conducted experiments using a common hammer drill and carbide-tipped bit to isolate the effect of drill bit wear on worker exposure to these hazards. The tests found that bit wear reduced worker productivity - holes took longer to drill - while increasing the drill operator's exposure to silica dust, noise, force and vibration. Looked at another way, by swapping out worn bits promptly for sharp new ones, contractors can increase productivity while better protecting workers from occupational health hazards.

The results have been published in a series of journal articles. Click on the links below for a one-page summary of the key findings: