(1) Caution signs shall be so placed on the track
or car as to give necessary warning to persons approaching car from open end or
ends of siding. These signs shall be left up until after car is unloaded and
disconnected from discharge connections. Durable signs shall be at least 12 by
15 inches in size and bear the words "Stop-Tank Car Connected"
or "Stop-Men at work". The word "Stop" shall be in
letters at least 4 inches high and the other words in letters at least 2 inches
high on a background of contrasting color.
(2) The track of a tank car siding shall be
(3) Brakes shall be set and wheels blocked on
all cars being unloaded.
(4) Tank cars of anhydrous ammonia shall be
unloaded only at permanent storage locations.