Flatulence Etiquette

Can someone please tell me what the proper etiquette is for public flatulence? Well, maybe not actually out in public, but in the presence of others?
I was assaulted over the weekend, not once, but twice! I'm not even going to talk about the first episode, I'm willing to let that person slide on their "incident", but the second episode... well!!
Granted, my husband assaults me on pretty much a daily basis. While I don't like it, I've become used to it. Or at least, I've become used to his crude behavior because let's face it, one can never really get used to the smell of vaporized feces.
Anyway... last night, a person I know was standing a couple of feet away from me. We were in a living room, just the two of us, when this person let one rip. I'm like, "oh my God! Excuse you," and I quickly stepped away. That person barely even acknowledged what they had done.
Not two minutes later, we're standing at the kitchen counter, and they did it to me again!!
Now I was getting really irked! I repeated my words from before and said, "Can't you at least say 'excuse me', and step away?"
With that, the offender said, "Oh, excuse me."
"Well it's a little late for that now!!"
I was running out of rooms to escape to that didn't have polluted air.
Arghhh!
Honestly, if you feel a pooter coming on, shouldn't you try to either go to the bathroom, go outside, or at least step away from anyone that is close to you?
And if you truly feel that by stepping away, it's going to make the flatulence noise worse, couldn't you at least ask the other person to step away?
I realize that occasionally, a fart sneaks up on us when we least expect it and just slips out. But gimme a break!!, how hard is it to say, "Excuse me", or "I'm sorry"?????
Mind you, I'm not talking about the sneaky, quiet ones that just slip out. I'm talking about the loud ones that can't help but be heard.