9. Risk Group 3 Safety
•
HD as discussed in "High Brightness precautions: Hazard Distance (HD)", page 6 , relevant for intrabeam exposure.
•
HDre
fl
ection : the distance that has to be kept restrictive related to the re
fl
ected light from the rear projection screen.
•
HDdiffuse : the relevant distance to be considered while observing the defuse surface of the rear projection screen.
As described in "High Brightness precautions: Hazard Distance (HD)", page 6 , it is mandatory to create a restricted zone within
the beam areas closer than any NOHD. In the enclosed projection area the combination of two restricted zones are relevant: The
restricted zone of the projected beam toward the screen; taking into account 1 meter Separation Width (SW) from the beam onward.
Combined with the restricted zone related to the rear re
fl
ection from the screen (HDre
fl
ection); also taking into account a 1 meter
lateral separation.
The HDre
fl
ection distance equals 25% of the difference between the determined HD distance and the projection distance to the rear
projection screen. To determine the HD distance for the used lens and projector model see graphs in chapter "HD in function of the
lens Throw Ratio (TR)", page 8 .
HDre
fl
ection = 25% (HD – PD)
The light emitted from the screen within the observation shall never exceed the RG2 exposure limit, determined at 10 cm. The
HDdiffuse can be neglected if the measured light at the screen surface is below 5000 cd/m² or 15000 LUX.
9.5
HD in function of the lens Throw Ratio (TR)
TR (Throw Ratio)
The ratio of the distance to the screen (throw) to the screen width.
HD versus Throw Ratio
0
0,2
0,4
0,6
0,8
1
1,2
1,4
1,6
1,8
0,5
0,9
1,3
1,7
2,0
2,3
2,7
3,1
3,5
3,9
4,3
4,7
5,1
5,5
5,9
6,3
6,7
7,1
7,5
Hazar
d
Distance
[m
]
Throw Rao
Hazard Distance Thermal Acidental Exposure
Image 9-4
Hazard Distance in meters versus Throw ratio of the lens for the Balder projector
Graphs shows Hazard Distance in meters versus Throw ratio of the lens
54
601–0442 BALDER 13/09/2017
Summary of Contents for Balder
Page 1: ...Balder Installation Manual 601 0442 00 13 09 2017 ...
Page 32: ...3 Physical Installation 28 601 0442 BALDER 13 09 2017 ...
Page 44: ...6 Advanced picture adjustments 40 601 0442 BALDER 13 09 2017 ...
Page 52: ...7 Installation menu 48 601 0442 BALDER 13 09 2017 ...
Page 54: ...8 Status menu Lists the projector IP address 50 601 0442 BALDER 13 09 2017 ...
