Hi there. Based on other posts, I've sort of established that the HIV virus dies/becomes ineffective almost instantaneously upon contact with air. If this is indeed the case, by right the vaginal fluids near the vaginal opening and even slightly inside the vaginal should be incapable of transmitting HIV as it would definately be somewhat exposed to air upon penetration. As such, is there a general guide as to how deep can a unprotected penis penetrate a vaginal without being exposed to vaginal fluids that ae capable of transmitting HIV?