oxygen has no colour
Green for fresh water"« Crimson red for steam"« Signal red for fire fighting"« Dark brown for oils or combustible liquids"« Orange for chemicals"« Light blue for air"« Black for process effluents (drain / vent/ flare, etc)Gas Cylinders"« Black for oxygen"« French gray for Nitrogen"« Maroon for acetylene
oxygen it has no colour, taste or smell.
Black
In the hospital, oxygen is supplied to each patient room via an outlet in the wall. Oxygen is delivered from a central source through a pipeline in the facility. A flow meter attached to the wall outlet accesses the oxygen.
CLEAR
Yellow
Hemoglobin
oxygen
red
colour
i would check out the Russian pipeline or the Alaskan pipeline.