Control of Wood Dust from Automated Routers

Abstract

An association between nasal cancer and occupations involving exposure to wood dust has been clearly established in the literature. Therefore, it was deemed necessary to conduct research to develop new and improved methods for controlling this dust. This article reports on the research that has been conducted by scientists at the National Institute for Occupational Safety and Health (NIOSH) on automated routers. A computer-controlled jet stripper system was developed to reduce the wood dust emissions from automated, multidirectional routers. The system consists of a set of 24 jets, combined into 8 operational units which are uniformly located around the entire inside periphery of the brush holder above the worktable. The jets are supplied with pressurized air and are activated by pneumatic valves as needed. The system is also effective in controlling the wood dust from conventional, one-dimensional routers, especially when routing is performed under the upper surface of the workpiece and provided that local exhaust hood and brush are installed at the router head. In this case, the jet stripper, consisting of 18 jets, is located inside the brush holder periphery close to the worktable and the routed wood. Laboratory results were confirmed by field tests conducted on a computer numerically controlled router performing multidirectional routing. The developed control system, combined with presently used controls (i.e., a brush and local exhaust installed at the router head), reduced the wood dust emissions by over 90 percent. The new control system does not interfere with the worker's activity, requires no special maintenance, and is inexpensive to install and operate.