I always thought getting a bj was absolutely safe. In fact, I would do this as opposed to protected vaginal sex because I was worried that if the condom broke, it was very unsafe. So what is safer - unprotected bj or protected vaginal sex?
Protected insertive penile-vaginal sex is considered safe if the latex condom is used properly and doesn't fail (break).
Unprotected insertive oral sex carries a very low risk for HIV acquisition.
If the condom fails during penetrative protected vaginal sex, the HIV-acquisition risk then increases to greater than unprotected oral sex.