A colostomy is an opening (stoma) in the large intestine (colon), or the surgical procedure that creates one. The opening is formed by drawing the healthy end of the colon through an incision in the anterior abdominal wall and suturing it into place. This opening, often in conjunction with an attached ostomy system, provides an alternative channel for feces to leave the body. Thus if the natural anus is unavailable for that function (for example, in cases where it has been removed in the fight against colorectal cancer or ulcerative colitis), an artificial anus takes over. It may be reversible or irreversible, depending on the circumstances.
My brother has terminal rectal cancer, and he has a colostomy bag. He feels humiliated in quiet waiting rooms with other people when his bag starts making fart sounds. I'm trying to find a material to enclose his colostomy bag to dampen the sounds. There's a company that sells neoprene foam...