Dust Control Handbook for Industrial Minerals Mining and Processing

Hydraulic hollow cone nozzles. In wet spray systems, nozzles used to produce a circular ringspray pattern, typically producing smaller drops than other hydraulic nozzle types of the sameflow rate.Hydrogen embrittlement. A process where metal (high-strength steel) can become brittle andfracture due to exposure to a hydrogen source.Hygroscopic. The ability to absorb moisture from the air.Impact plate. When material is being conveyed, a device used to control the direction and speedof the material.Impingement plate scrubber. A type of wet scrubber in which the dust-laden air passes upwardthrough openings in perforated plates, which hold a layer of water.Induction. Airflow or product movement that creates sufficient momentum energy to pulladditional surrounding air into the airflow or product movement.Inhalable dust. A fraction of airborne dust intended to represent those particles likely, wheninhaled, to be deposited in the respiratory tract from the mouth and throat to the deep lung. Thecollection efficiency of an inhalable dust sampler varies by aerodynamic diameter of theparticles—to demonstrate, about 50 percent of 100-micrometer particles (but nearly 100 percentof particles less than 1 micrometer) are collected.Inlet loading. In ventilation systems, the amount of dust traveling to the collector.Intake air. In ventilation systems, the clean air supplied into an area or space to replace existing(contaminated) air.Laminar. Sometimes referred to as streamline flow, the occurrence of air flowing in parallelpaths with no disruptions between the paths.Local exhaust ventilation (LEV). A system used to capture dust and remove it from a mine orplant environment. The concept is to capture dust-laden air, pull this air into an exhaust hood,transport the dust-laden air through ductwork to some type of dust collection system, and ductthe dust-free air to some type of exhaust fan, which creates negative pressure, resulting in theairflow for the entire system.Makeup air. In ventilation systems, the clean air necessary to supply a specific ventilationapplication (e.g., a local exhaust ventilation system).Mechanical shaker collector. In dust collection systems, a type of collector that uses mechanicalshaking to remove the excess dust cake from the collection media.Musculoskeletal Disorder (MSD). Health problems in the body's muscles, joints, tendons,ligaments, and nerves. When work-related, these problems are caused by the work process orenvironment.280 Glossary