ANSI ISEA Z87-1:2020 pdf free download – American National Standard Occupational and Educational Personal Eye and Face Protection Devices
prescription lens (Rx). A lens manufactured to the wearer’s individual corrective prescription. prescription lens carrier. A lens housing for mounting prescription lenses behind a protective lens. prismatic power, “prism”. A measure of the angular deviation expressed in prism diopters ( D ) of a light ray after passing along the viewing path through a lens. One prism diopter equals a devia- tion of 1 cm per meter of path length. protector. A complete device meeting, at a min- imum, the requirements of Section 5 of this standard. reader. A mass produced non-prescriptive spec- tacle that incorporates plus refractive power in a portion of the lens. refractive power, “power”. A measure of the ability of a lens to focus light rays, expressed in diopters (D). removable lenses. Lenses fabricated to fit a sin- gle spectacle frame. replaceable lenses. Lenses intended by the manufacturer to be interchangeable by the user. representative test lenses. Lenses produced of the same material(s), coatings, minimum thick- nesses, lens surfacing and framing processes as used by the manufacturer. resolving power. The measure of the ability of a lens to form separate images of two objects close together. retained. In this standard, the use of the word “retained” means that the lens is not separated or visibly displaced from the frame by more than 25% of its intended mounting structure or sup- port.
NOTE: During short term exposure to light, the dis- comfort of bright light is approximately proportional to the product of the illuminance at the eye and time. The time dependence of the darkening process can differ for different designs of filters where the lumi- nous transmittance varies with time. It is therefore appropriate to define the response time of an automatic darkening filter lens as an integral of the luminous transmittance over time and not merely by the initial and final luminous transmittance. temple. A spectacle component that extends par- tially around the head or behind the ear of the wearer. tinted lens. A lens with color such as amber, smoke, or cobalt which may not meet the re- quirements of Table 7, 8, 9 or 10. type tests. One or more tests performed on an item to approve a material, construction, model or design to determine if it is capable of meeting the requirements of a product standard. ultraviolet radiation (UV). Electromagnetic energy with wavelengths from 200 to 380 na- nometers. variable tint lens. A lens which darkens or fades by some mechanism, excluding automatic dark- ening welding filters. These are typically photo- chromic lenses and may or may not meet the re- quirements of Table 7, 8, 9 or 10. visible light filter. A filter lens intended for the attenuation of visible light. This may be a sun- glass or special purpose lens.