As the name suggests, parking brake is meant for when the vehicle is parked somewhere. But I tried using it at the red light and it disengages itself as soon as I press the gas/accelerator pedal. I am wondering, is it safe to use parking break at the red light? In this way I don't need to keep my foot on the break all the time while my vehicle is at complete stop. Please let me know. I didn't see anything mentioned in the owners manual.

 

It's fine to use, it's AUDI's version of hill assist.