Studies of the association between noise and outcomes not related to hearing disease are usually based on analogies to the hearing effects of noise, and the maximum exposure limits for hearing effects (85 dB(A)) is usually also considered for non-hearing outcomes [ 11].
Measurements of respirable crystalline silica in the UK construction industry have found levels that greatly exceed the current maximum exposure limit of 0.3 mg m−3, particularly for work in confined spaces and without water suppression of dust or effective extraction (Chisholm, 1999).
The incident power on the cornea was adjusted to 610 µW, which is for this wavelength below the maximum exposure limit, given by laser safety standards.
The recommended maximum exposure limits are a) 18 µg Cd for a 6-hr saline extraction to simulate mouthing of items, and b) 200 µg Cd for a 24-hr extraction in dilute hydrochloric acid (HCl) to simulate ingestion of an object by a child (U.S. CPSC 2010e).
The average human exposure to ambient ultraviolet radiation is around 25 kJ/m/year (in the USA) [ 40] and the ANSI standard maximum permissible exposure limit for photochemical damage for a point source laser beam at 355 nm is 1 J/cm2 [ 41].
He said that while the government set maximum radiation exposure limits for plant workers at 250 millisieverts per year, his company set its own standard of 20 millisieverts.
REL = Recommended Exposure Limit for workers.
Maximum recommended occupational exposure limits for an 8-hr workday are 5,000 ppm as a time-weighted average, for the Occupational Safety and Health Administration (OSHA 2012) and the American Conference of Government Industrial Hygienists (ACGIH 2011).
The National Institute for Occupational Safety and Health has exposure limits for benzene, benzopyrene and naphthalene, which are known carcinogens.
In this study, given 1-W incident power and 2 mm beam diameter, the laser irradiance was ~32 W/cm and the maximum exposure duration for safety limit was ~0.1 s.
