Direct-reading instruments are valuable tools for detecting and
measuring worker exposure to hazards such as gases, vapors,
aerosols, surface contamination, musculoskeletal disorders, and
radiation. These instruments provide on-site measurement of
exposures in units (such as parts per million parts of air, or
ppm) that indicate whether or not the exposures pose an
occupational health or safety risk and if the prevention methods
employed are actually providing the proper level of protection.
There are many types of instruments available, each of which is
designed for a specific monitoring purpose. For example, NIOSH
developed a new personal dust monitor (PDM) in collaboration
with manufacturers, labor, and industry for assessing miners’
exposure to coal dust in underground coal mines. The first
advancement in more than 30 years for monitoring coal dust
exposures, the PDM provides real-time exposure data during a
work shift. It warns of potential over-exposures in time for
mine operators to reduce exposures tha