why are my husbands farts so awful?

my husband permanently has the most rancid, stomach churning gas possible. I've honestly dry heaved before. He lets these off at about 20 minute intervals with no warning and usually with a family guy style sound. its actually becoming a problem because I can't sit in my own house without being stink bombed. it smells quite sulphuric but with a lingering smell of arse afterwards. I'm genuinely concerned he might have a bowel problem but he laughs it off and refuses to consider it as anything other than hilarious. does anyone else have this problem? how do you cope with the eye watering selfishness? and is it a sign of something more serious, like something has crawled up him and died?