I suppose this is a good point at which to recall the "IBM coathook" story.
IBM once had a part number for a coathook.
Once upon a time, when the world was young and mainframes filled whole rooms, there was an IBM part number for a coathook.
In spite of filters for the cooling air, the interior of mainframes would collect dust, and all the grotty things that are in dust. Said interiors were where techs had to work to find and fix problems, and IBM techs were professionals in a primitive age that demanded white shirts, jackets, and ties. To allow their techs to work without spoiling their handsome IBM jackets, the mainframes were equipped with a coathook inside where the tech's coat could be safely hung, but only after the mainframe's door was securely closed!