1.  Air pressure in laboratories and animal care rooms should be negative in relation to the corridor or adjacent non-laboratory areas. Rooms housing immunocompromised animals should be at a positive pressure with respect to adjoining areas. Consult with SU Fire Marshall for design details.

_{CDC-NIH Biosafety in Microbiological and Biomedical Laboratories (ABSL 2, D.5)}

_{Good Practice per Stanford EH&S}

Potentially harmful aerosols can escape from the containment of the laboratory room unless the room air pressure is negative to adjacent non-laboratory areas. As a general rule, air should flow from low hazard to high hazard areas.

2.  Dedicated sterile tissue culture rooms should be balanced neutral or slightly positive with respect to adjoining areas. Tissue culture rooms that involve the use of biohazardous agents shall be negative as stated in C-1 above.

_{Good Practice per Stanford University EH&S}

This will minimize the potential for possible contamination of experiments within these rooms.

3.  An autoclave should be provided with a canopy hood, slotted exhaust, or other suitable means of local exhaust. In addition, autoclave rooms should have a minimum of 10 air changes per hour.

_{Good Practice per Stanford University EH&S}

Unpleasant heat and odors will linger in the room unless provided with effective local exhaust and adequate frequency of air changes.