R5910886 /02
G60
9
1.4.2 High Brightness precautions: Hazard Distance (HD)
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
“
”
,
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
RZ
HD
SW
1
m
SW
SW
SW
HD
EXIT
SH
RA
PR
TH
RZ
SH
(B) TOP VIEW
(A) SIDE VIEW
Image 1-2
A
Side view.
B
Top view.
RA
Restricted Access location (boot area of projector).
PR
Projector.
TH
Theater.
RZ
Restriction Zone in the theater.
SH
Separation Height.
SW
Separation Width.
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 sufficient separation height or by placing barriers. The
minimum separation height takes into account the surface upon which persons other than operator, performers or employees are
permitted to stand.
On Image 1-3 a typical setup is displayed. It must be verified if these minimum requirements are met. If required a restricted zone (RZ) in
the theater must be established. This can be done by using physical barrier, like a red rope as illustrated in Image 1-3.
The restricted area sticker can be replaced by a sticker with only the symbol.
