R5906112 /09 UDX series 171.4 High Brightness precautions: Hazard Distance(HD)HDHazard Distance (HD) is the distance measured from the projection lens at which the intensity or theenergy per surface unit becomes lower than the applicable exposure limit on the cornea or on theskin. The light beam is considered (to be) unsafe for exposure if the distance from a person to thelight source is less than the HD.Restriction Zone (RZ) based on the HDThe HD depends on the amount of lumens produced by the projector and the type of lens installed. Seechapter“HD in function of modifying optics”, page 21.To protect untrained end users (as cinema visitors, spectators) the installation shall comply with the followinginstallation requirements: Operators shall control access to the beam within the hazard distance or install theproduct at the height that will prevent spectators' eyes from being in the hazard distance. Radiation levels inexcess of the limits will not be permitted at any point less than 2.0 meter (SH) above any surface upon whichpersons other than operators, performers, or employees are permitted to stand or less than 1.0 meter (SW)lateral separation from any place where such persons are permitted to be. In environments whereunrestrained behavior is reasonably foreseeable, the minimum separation height should be greater than orequal to 3.0 meter to prevent potential exposure, for example by an individual sitting on another individual'sshoulders, within the HD.These values are minimum values and are based on the guidance provided in IEC 62471-5:2015 section6.6.3.5.The installer and user must understand the risk and apply protective measures based upon the hazarddistance as indicated on the label and in the user information. Installation method, separation height, barriers,detection system or other applicable control measure shall prevent hazardous eye access to the radiationwithin the hazard distance.For example, projectors that have a HD greater than 1 m and emit light into an uncontrolled area wherepersons may be present should be positioned in accordance with “the fixed projector installation” parameters,resulting in a HD that does not extend into the audience area unless the beam is at least 2.0 meter above thefloor level. In environments where unrestrained behavior is reasonably foreseeable, the minimum separationheight should be greater than or equal to 3.0 meter to prevent potential exposure, for example by an individualsitting on another individual's shoulders, within the HD. Sufficiently large separation height may be achievedby mounting the image projector on the ceiling or through the use of physical barriers.Safety
