That isn't an 'autoclave' (I don't actually know what one is), it is a bedpan sanitizer, I work in an adult home care facility and we have the same thing, only newer. I have found these in many other abandoned hospitals as well. when you open the door, you stick a soiled bedpan in and the two arms inside hold it in place when you close the door, then you depress the foot pedal and water rushes over the bedpan until it is sterilized.