In the course of manufacturing chromed bumpers for the automotive industry, close visual inspections are carried out at several stages to ensure that an acceptable finish is achieved. The areas where such inspection tasks are carried out are extremely brightly illuminated with fluorescent lights to the point where visible light intensities are comparable to outdoor, open-shade, noonday light levels. It had been reported that small cataracts (of the type described as posterior subcapsular opacities) were observed by an optometrist in the eyes of one of the inspection workers during a routine eye examination for prescription lenses. Although it was stated that these were not sufficiently large to impair the individual's vision, it was also pointed out that an association has been reported between cataracts and exposure to ultraviolet (UV) radiation. Fluorescent lamps used for lighting produce most of their output in the visible part of the spectrum but have been shown to emit UV as well in varying degrees depending on the lamp type and the type of glass used in the envelope. Some fluorescent lamps are more specifically designed to be used for tanning and have fairly high UV emission levels comparable to those found in sunlight outdoors. More generally, the relatively high visible light levels in the inspection areas gave rise to some concerns among the workers that those levels might be above tolerable limits.
RHSC carried out measurements to establish whether or not visible light levels in any of the inspection areas might be above tolerable limits or accompanied by ultraviolet emissions sufficient to result in worker exposures in excess of recommended limits. The effectiveness of eyewear provided to workers was also evaluated. RHSC reported the results discussing the significance of the observed levels comparing them to levels in other occupational, commercial and residential environments.