|
Type of Distribution
|
Semi-cut-off
Sodium
150W SOX
|
B.S. 1788:1964
requirements
|
|
Downward light output ratio
|
92.45%
|
|
Angle of elevation
Upper limit of beam
Lower limit of beam
|
76%
60%
|
75% must be within beam
|
Peak intensity ratio
|
2.17
|
1.8 - 4
|
Maximum and minimum intensity
ratio in the zone from the
downward vertical to 30° therefrom
|
1.055 max.
.616 min.
|
not to exceed 1.7
not less than 0.3
|
Angle of elevation at which the
intensity ratio is 1.2 in the vertical
plane parallel to the street axis
|
83°-30'
|
between 80°-86°
|
Intensity ratio at the horizontal
in the vertical plane parallel to
the street axis.
|
.486
|
not to exceed 0.7
|
Light output in lower hemisphere
(downward flux lumens)
|
12,475
|
See CP 1004
Part 2:
1963 tables
|
