An official website of the Washington state government
The .gov means it’s official.
A .gov website belongs to an official government organization in the United States.
The site is secure.
The https:// ensures that you are connecting to the official website and that any information you provide is encrypted and
transmitted securely.
Working together for safer communities
A respirator in which the air pressure inside the respiratory-inlet covering is positive during exhalation in relation to the air pressure of the outside atmosphere and negative during inhalation in relation to the air pressure of the outside atmosphere.