As nouns the difference between standpipe and sandpipe
is that standpipe is a vertical pipe into which water is pumped so that a desired pressure is available at the bottom while sandpipe is a pipe conveying sand, as in a steam locomotive, where it deposits sand directly in front of the driving wheels to aid traction.
standpipe
English
Noun
(
en noun)
A vertical pipe into which water is pumped so that a desired pressure is available at the bottom.
# A vertical pipe used as an overflow protection drain in certain domestic plumbing fixtures (e.g. flush toilets).
The water supply of a building for the use of firefighters.
sandpipe
English
Noun
(
en noun)
A pipe conveying sand, as in a steam locomotive, where it deposits sand directly in front of the driving wheels to aid traction.