Hard to hide a gas explosion... However,

A good strategy that I've learned is to take a dump 1 or 2 hours before the session.  
If after 10-30 minutes, I'm still ok, then that means there are no radioactive materials in my body to cause gas.  If after 10-30 minutes, I still need to take another dump, then it's even better since I'm now very sure that every fart catalyist and fart raw ingredients are out of me.  I jump in the shower and clean up my ding hole real good.  

As for hiding it during a session, it's next to impossible to hide it. Best to just aim it at the girl's nose and let it rip. She's appreciate it tremendously because I have read that recent studies from podunk univerisity show women are turned on by gas especially when injected close to their nose.  rof

Never gotten a loud one but have been "treated" to the stink.  I've had the urge while getting a BBBJ but always pucker up and hold it in.  Problem is, doing it is the opposite of letting yourself come.
My ex always claimed her farts were "sweet."  I beg to differ.
What's funny about women is so many want you to believe they don't fart.  My ex claimed she had "air in my back."  I explained that wasn't possible.  Then I caught her on the bathroom floor on her hands and knees, trying to fart.

Besides the Shower and Shave, I do a self Colon Cleansing. This way I know there won't be any problems during the Session.

No, but I've noticed a lot of queefing whilst fucking.....

seems natural enough to me  -  but I have had a few providers very embarrassed by it (or maybe it was uncomfortable?)  who wanted to change positions....