Effective dust control systems on concrete dowel drilling machinery

• Published in: Journal of occupational and environmental hygiene Vol. 13; no. 9; pp. 718 - 724
• Main Authors: Echt, Alan S., Sanderson, Wayne T., Mead, Kenneth R., Feng, H. Amy, Farwick, Daniel R., Farwick, Dawn Ramsey
• Format: Journal Article
• Language: English
• Published: England Taylor & Francis 01.09.2016; Taylor & Francis LLC
• Subjects: Air Pollutants, Occupational - analysis; Concrete dowel drilling; Concretes; Construction Industry; Construction Materials; Control systems; crystalline silica; Drilling; Drilling & boring machinery; Dust; Dust - prevention & control; Dust control; dust control systems; Effectiveness; Environmental Monitoring; Exposure; Hazardous materials; Inhalation Exposure - analysis; Inhalation Exposure - prevention & control; Measuring instruments; Meters; Occupational Exposure - analysis; Occupational Exposure - prevention & control; Occupational safety; Particulate Matter - analysis; respirable dust; Sampling; Studies; System effectiveness; Systems analysis; USA; Concrete dowel drilling; dust control systems; respirable dust; crystalline silica
• ISSN: 1545-9624; 1545-9632
• DOI: 10.1080/15459624.2016.1177644

Rotary-type percussion dowel drilling machines, which drill horizontal holes in concrete pavement, have been documented to produce respirable crystalline silica concentrations above recommended exposure criteria. This places operators at potential risk for developing health effects from exposure. United States manufacturers of these machines offer optional dust control systems. The effectiveness of the dust control systems to reduce respirable dust concentrations on two types of drilling machines was evaluated under controlled conditions with the machines operating inside large tent structures in an effort to eliminate secondary exposure sources not related to the dowel-drilling operation. Area air samples were collected at breathing zone height at three locations around each machine. Through equal numbers of sampling rounds with the control systems randomly selected to be on or off, the control systems were found to significantly reduce respirable dust concentrations from a geometric mean of 54 mg per cubic meter to 3.0 mg per cubic meter on one machine and 57 mg per cubic meter to 5.3 mg per cubic meter on the other machine. This research shows that the dust control systems can dramatically reduce respirable dust concentrations by over 90% under controlled conditions. However, these systems need to be evaluated under actual work conditions to determine their effectiveness in reducing worker exposures to crystalline silica below hazardous levels.