High Brightness Precautions: Hazard Distance - Barco Njord Installation Manual

Risk group 3 Safety

18.3 High Brightness precautions: Hazard Distance

HD
Hazard Distance (HD) is the distance measured from the projection lens at which the intensity or the
energy per surface unit becomes lower than the applicable exposure limit on the cornea or on the
skin. The light beam is considered (to be) unsafe for exposure if the distance from a person to the
light source is less than the HD.
Restriction Zone (RZ) based on the HD
The HD depends on the amount of lumens produced by the projector and the type of lens installed. See
chapter "HD in function of modifying optics", page 209.
To protect untrained end users (as cinema visitors, spectators) the installation shall comply with the following
installation requirements: Operators shall control access to the beam within the hazard distance or install the
product at the height that will prevent spectators' eyes from being in the hazard distance. Radiation levels in
excess of the limits will not be permitted at any point less than 2.0 meter (SH) above any surface upon which
persons 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 where
unrestrained behavior is reasonably foreseeable, the minimum separation height should be greater than or
equal to 3.0 meter to prevent potential exposure, for example by an individual sitting on another individual's
shoulders, within the HD.
These values are minimum values and are based on the guidance provided in IEC 62471-5:2015 section
6.6.3.5.
The installer and user must understand the risk and apply protective measures based upon the hazard
distance 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 radiation
within the hazard distance.
For example, projectors that have a HD greater than 1 m and emit light into an uncontrolled area where
persons 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 the
floor level. In environments where unrestrained behavior is reasonably foreseeable, the minimum separation
height should be greater than or equal to 3.0 meter to prevent potential exposure, for example by an individual
sitting on another individual's shoulders, within the HD. Sufficiently large separation height may be achieved
by mounting the image projector on the ceiling or through the use of physical barriers.
RA TH
PR
SH
RZ
LRZ
(A) SIDE VIEW
Image 18–1
A Side view.
B Top view.
RA Restricted Access location (boot area of projector).
PR Projector.
Based on national requirements, no person is allowed to enter the projected beam within the zone between
the projection lens and the related hazard distance (HD). This shall be physically impossible by creating
206 R5913593 /01 Njord
SH
(B) TOP VIEW
TH
RZ
SH
SW
TH
RZ
RA
SW
PR
SW
LRZ
Theater.
Restriction Zone in the theater.
Separation Height.
Separation Width.
SW
SW