ANSI Z80.36 pdf free download
ANSI Z80.36 pdf free download.Light Hazard Protection for Ophthalmic Instruments.
5.2.1 Requirements for classification as Group 1 for a scanning instrument
An ophthalmic instrument that images the retina or the anterior segment of the eye by using a small moving
irradiated area shall be classified as a Group 1 instrument for retinal visible and infrared radiation thermal hazard if the following limit is met: The weighted retinal visible and infrared radiation energy entering the eye shall be less than or equal to 1.32 mW.
NOTE 1.32 mW is the limit value given by 5.5.2.1 for weighted visible and infrared radiation (table 5) for a retinal image size of 0.03 mm and an exposure duration of 10 s, i.e., 1874 J/cm2.
An ophthalmic instrument that scans the retina shall be classified as a Group 1 instrument for photochemical aphakic light hazard if the value of the aphakic weighted retinal irradiance, EAR, meets the following requirement: EA..R shall be equal to or less than the limit given by 5.4.1.3 (table 2). Calculation of FA..R shall be done using a value of the retinal spectral irradiance, EA, that is found by dividing the power (given in watts, W) entering the eye at each wavelength interval, AA, by the area of the irradiated retina (given in cm2).
5.3 RequIrements for Group 2 instruments
5.3.1 If an instrument does not fulfil all requirements for a Group 1 instrument, it shall be checked for compliance with Group 2 requirements only for those hazards for which it did not fulfil the requirements of Group 1. The reporting requirements of clause 7 (b) need only be complied with if Group 1 requirements are not fulfilled for 5.4.1.1 — Weighted corneal and lenticular ultraviolet radiation irradiance (table 2), or 5.4.1.2 — Unweighted lenticular ultraviolet radiation radiant exposure (table 2), or 5.4.1.3 — Retinal photochemical aphakic light hazard, Weighted retinal irradiance (table 2).
Visible light is necessary for diagnosis of ocular pathology, and thus is commonly used in instruments such as direct and indirect ophthalmoscopes, slit-lamp microscopes, operation microscopes and endoilluminators. It is not reasonable to set limits on visible radiation that is needed for the diagnosis of disease or for visualization during ocular surgery. A surgeon may have to exceed an exposure level that is known to be potentially hazardous during an extended complicated surgery or a clinician may have to exceed an exposure level that is known to be potentially hazardous during an extended ocular examination for diagnosis of ocular pathology. With this in mind, the standard requires that the time to reach a potentially hazardous exposure be given, rather than to set a limit, so that clinicians are informed about potential optical radiation hazards that may be associated with the use of their instruments should they need to use an amount of radiation that has a high likelihood of causing ocular tissue damage.
When using the requirements of 5.5.2.1 the value of N, the number of pulses, is the number of times the scan passes over the circular aperture of 0.03 mm on the retina.
A scanning instrument that does not fulfil the requirements of 5.2.1 for photochemical aphakic light hazard shall fulfil the requirements of clause 7 (b)(1) for reporting time to reach the recommended maximum exposure using the procedure of 6.5.3 in which the value of EA.R shall be found using the procedure given in 5.2.1.
5.3.3 Group 2 instruments shall comply with the emission limits given in 5.5.
5.3.4 The test methods used for determination of compliance shall be in accordance with 6.3 and 6.4. However, if components that are being used in the instrument, e.g., lamps, light-emitting diodes, nonremovable filters, lenses, fibres, etc., prevent some, but not all, emissions specified for Group 2, then provided that documentation of test certification of the respective components is available, measurements shall be required only for those parameters in tables 4 and 5 where the components do not prevent the limits from being exceeded.
5.3.5 Where provision is made to vary the brightness of the Group 2 instrument, an indication of the maximum intensity and fractions of maximum intensity shall be provided on the instrument.
5.3.6 Information shall be supplied with Group 2 instruments, as specified in Clause 7.ANSI Z80.36 pdf download.
