A PHA is an OSHA directive that identifies safety problems and risks within a process,develops corrective actions to respond to safety issues, and preplans alternative
emergency actions if safety systems fail. The PHA must be conducted by a diverse team that has specific expertise in the process being analyzed. There are many
consulting and engineering firms that also provide PHA services. PHA methodologies can include a What-If Analysis, Hazard and Operability Study (HAZOP), Failure Mode
and Effects Analysis (FEMA), and a Fault Tree Analysis.