Presumably they're arbitrarily-designated based on what the room's use is. I use the Kaitai Shinsho's room names because they're more descriptive than other guides (eg. the Slaughterhouse in RE4 is known to other people as the "torture shed", so they have no idea that it's an abattoir).
You may want to consider getting familiar with our MoS for rooms and room names before editing more, otherwise it appears we're going to eventually have to edit over most of your work to bring it up to standards. This is not to antagonize you or anything, we want to help you help us by making correctly formatted edits.