When is it safe to fart in front of a girl

the classy answer would be never

but, I am not a classy guy

and NO, I dont have any experience or funny anecdotes to amuse the masses

I was just wondering
when would it be a safe time to fart?
you know, you have to prove you are not perfect
you are a human, you all have needs..so...
when? After the 3rd date
after you get intimate for the first time...
I dunno

anyone help me?