I Am curious if a person did a shot of vodka how long until he would pass a clear. Urinalysis?

I'm curious why someone subject to getting a urinalysis would even think about taking a shot of vodka.

No one will advise an alcoholic that they can just have one shot of anything because even that is one to many.

That depends. Is the urinalysis testing for EtOH or EtG?

Also, if that person has a continuous previous use, it can take longer. Also what is the cut off range for "passing"