HAZOP stands for "Hazard and Operability Study" and is a systematic way to identify and address potential hazards in industrial processes before an incident occurs that could affect the safety of people or assets while hindering productivity. It is a form of risk management to identify, evaluate, and control hazards and risks in complex processes. HAZOP studies are typically performed while new facilities are being designed and constructed, when new processes are added, or when processes change. Most regulatory agencies also require periodic HAZOP studies on existing processes.

The HAZOP assessment is typically performed by a small team that breaks each step of a process down for individual review to identify potential deviations from the original process design. The process is broken down into small, manageable sections called "nodes," and every variation in work parameters is considered for each step to see what could go wrong. The HAZOP method involves brainstorming potential scenarios that deviate from the original process design, defining what might cause such a scenario, and identifying the consequences of the scenario.

HAZOP is a common hazard analysis method for complex systems, and it can be used to identify problems even during the early stages of project development, as well as identifying potential hazards in existing systems. The HAZOP technique is qualitative and aims to stimulate the imagination of participants to identify potential hazards and operability problems.