The construction workers operating enclosed cabs may be exposed to hazardous dust containing silica. The National Institute for Occupational Safety and Health (NIOSH) determined that exposure of machine operators can be reduced through modernization of the air pressurization systems and filtering present in the booths, the use of compounds to sweep the floors and implement programs to control dust.
Inhalation of crystalline silica dust can cause silicosis, a deadly lung disease. No effective treatment exists for silicosis, however, can be prevented by controlling the exposure of workers to dust containing crystalline silica. Exposure to crystalline silica has also been linked to lung cancer, kidney disease, decreased lung function and other disorders.
Many construction activities may generate dust crystalline silica polishing or cutting concrete, repairing masonry structures, using jackhammers to break concrete or excavation of mobile (eg., Drills, loaders, graders, dozer, straight blade grader and bridge cranes).
The cabins for the operators of the construction industry are made to protect operators from excessive noise and dust. When the equipment is new, the controls in the cockpit can usually reduce exposure to dust to an acceptable level. However, as the team goes getting old, many components of the control system deteriorates (eg sealing), which may cause the operator is exposed to hazardous levels of dust.
A study in a closed cabin of an old model used on the surface of a coal mine respirable dust indicated that the cabin was almost 13 times greater than the exposure levels recommended by NIOSH (REL).
NIOSH, in collaboration with the Administration of Mine Safety and Health (MSHA), mine operators and equipment manufacturers, has conducted studies on mining in the United States to determine the most economical and effective ways to reduce dust exposure operators who work in enclosed cabs.
Engineering controls and work practices identified in these studies are directly related to mobile equipment used in excavation of the construction industry. NIOSH therefore recommends that heavy construction will use the same working practices and the same controls for mobile equipment.
The main sources of dust in an enclosed cabin with little hermetic seal, are the airborne dust in the work area and dust that drags the operator himself. The two most important factors in reducing dust concentrations in enclosed cabs were the use of an air filtration system and an effective airlock (with positive seal) for a positive pressurization inside the cabin.
Tags: air filtration system, air pressurization systems, airborne dust, construction industry, control dust, crystalline silica dust, engineering controls, Hazardous Dust, respirable dust, silicosis