Several industry guidelines and standards are available for laboratory HVAC design. These tools offer guidance for the design and operation of laboratories but none of them specify the deliberate methods of evaluating design listed in the Process Safety Management (PSM) rule. Although not intended to be used as a design tool, process hazard analysis (PHA) offers designers a systematic approach to engineering for safety. PHA is the study of a facility, process, building, service or operation carried out to ensure that hazards are identified, understood and properly controlled. The requirements of this method are reviewed and some ideas on how to apply them to HVAC system design and operation are offered.