Evening star. [volume] (Washington, D.C.) 1854-1972, 1929-02-24

! The slowest thinking notorist driving
at the most rapid rate of speed can
avoid collision with the fastest run
ming train at grade crossing if he is
| given 90 seconds warming of the ap-
proach of the train. This is the basis
for minimum standard operating
time for automatic grade crossing sig
nails included in national standard
code devoted largely to colors for traffic
signals, Just published by the American
Standards Association. The code was
| formulated by committee of so traffic
safety, railway and signal engineers
working under the national standard
lzatlon procedure of the American
! Standards Association. with the Amer
lean Association of State Highway Off
Gals, the United States Bureau OF
Standards and the National Safety
Council, taking leading part in the
work.
The standard represents the results
OF i've years of study and research by
the members of the committee. accord
ing to the Standards Association. The
work OF this committee resulted in clari-
| lying the confusion in colors used in
traffic signals which existed at the time
in various parts of New York City
results was abandonment of the system
then in use on Fifth avenue in Man
haitian which made green "go" signal
for vehicles travelling in one direction
and stop" signal for vehicles travel
| in another direction.
| The color technOlogiStS on the COM
mittee left nothing to chance in setting
up standards for the colors for traffic
| signals. Red, yellow and green, the
only colorS recognized as permissible for
use in traffic signals, are carefully de-
! fined in terms of dominant wave lengths
of light, to assure that the manufac-
| turers of the signals will make the
colorS so accurate that all signals in a
community. no matter from how many
manufacturers they are purchased, viii
be exactly alike.
The standard permits the use Of
white, amber or yellow headlights. anc
stipulates that no red or green lights
| shall be displayed upon any vehicle ST
as to be visible from point directly ir
| front of it.
In reaffirming red as the color TO
/ tail lights the standard points out tina
red has been adopted only because o.
it's present universal use for this pur'
pose, but that it is not consistent with
the general Standardization of colors
and that if any change is made yellow
is recommended.
Other provisions of the standard in
clude yellow and not red or green ligh
signals shall be displayed on a vehiclI
to indicate the drivers intention Il
reduce speed or change direction. Non
luminous mechanical signals displayed
to indicate the drivers intention to re-
duce speed or change direction shall
consist of a semaphore which can b.
projected from the left side Of thu
vehicle. 1t is recommended that thu
position of the semaphore when pro
jected be limited to the horizontal
where definite forms of signs or signals
are used, either alone or in combina
ton with colors-(a) stop shall be in
dictated by having the greatest dimen
sion horizontal, as with a Horizontal
string of lights; (b) caution shall b.
indicated by having the greatest di
mention at an angle of As degrees with
the horizontal; (c) proceed shall be in
Dictated by having the greatest dimen
sion vertical. The standard also pro
vides that flashing signals shall be 81
constructed that they shall be visibl,
for a distance of at least 800 feet on {