clean room—
1. (also: white room) a room that is virtually free of dust or bacteria (used in assembly of precision equipment):
- The plant is a state-of-the-art facility that forms transistors onto large glass substrates, in a class–100 clean room.
2. (med.) operating theater with a “clean-room” atmosphere:
- It was a hospital clean room he was locked in. Purified air and the smell of disinfectant.
dirty room—(med.) an operating room where the surgeon has to deal with an infection:
- The hospital has four wards. In addition, there is an operation theater for major procedures, and a “dirty” room for minor cases.