Workstation design improvements for the reduction of dust exposures during weighing of chemical powders.
Appl Ind Hyg 1989 Sep; 4(9):227-233
Several modifications of the manual weight out workstation were tested as improvements to reduce dust exposures during the weighing of chemical powders. The layout of the worktable was evaluated and redesigned to improve process flow. A local ventilation hood was added on top of the bulk material drum. An air shower was also installed above the worker to control the eddy in front of the worker. A cost analysis determined the installation and operating costs of the modified controls. At the facility where the studies were performed, workers received powdered raw materials in 23 kilogram bags. They weighed out small quantities of the materials, less than a full bag, at a ventilated booth. Large bags were dumped into a drum and weighed into small paper bags. The small paper bags of powder were placed into a bin or a second drum for storage. The study indicated that with additional controls a basic ventilated booth was able to reduce dust exposures if configured correctly. The addition of the air shower could reduce the need for booth exhaust, lowering operating costs. Less makeup air was needed once the exhaust volumes were lowered. This cost saving was primarily of concern in the winter as makeup air must be heated. The workers perceived both the modified worktable with the local exhaust ventilation and air shower to be desirable.
NIOSH-Author; Dust-control; Workplace-studies; Airborne-particles; Control-technology; Ventilation-systems; Ventilation-hoods; Dust-control-equipment
Applied Industrial Hygiene