Читать книгу Patty's Industrial Hygiene, Physical and Biological Agents - Группа авторов - Страница 128

For actinic UV radiation, the maximum permissible exposure time is (15)

(24)

where E_eff (in W m⁻²) is defined in Eq. (10). The maximum permissible exposure time for blue‐light sources that subtend an angle greater than 0.011 rad is (20):

(25)

and the maximum permissible exposure time for blue‐light sources that subtend an angle less than 0.011 rad is (20):

(26)

Unlike the photochemical effects represented by the actinic UV hazard and the blue‐light hazard, thermal effects do not show a strictly reciprocal relationship between spectrally weighted irradiance or radiance and permissible exposure time. Viewing durations may be limited involuntarily to a few seconds by the aversion response or the sensation of pain. A worker performing a visual task might, however, be motivated to persist in viewing an excessively bright source despite eye discomfort.