Before revision: Conversely, particulates are prevented from escaping hazardous environments, such as nuclear reactors and some laboratories of biochemistry, by maintaining the room at a lower pressure than the surroundings, so that air (and any particulates that it carries) cannot escape easily.
After revision: Conversely, particulates are prevented from escaping hazardous environments, such as nuclear reactors , laboratories of biochemistry, and medical centers, by keeping negative room pressure - maintaining the room at a lower pressure than the surroundings, so that air (and any particulates that it carries) cannot escape easily.