Actually, that's not true at all. There are private IRBs for physicians that operate private practices who want to do clinical trials. They are faster, too. Instead of months, the private guys take a week.
The law states that there must be 5 members on an IRB...from differing backgrounds and one non-scientific member. The usually charge around $1500 to act as an IRB for a study. Now if I could do say three a week..meet weekly....that some nice supplemental income. Maybe. I'm really not that sure. We need to get a person on a commercial IRB on the mentor forum to tell me how much cash I could make from doing that....