HAZOP Studies / HIRA / QRA

Hazop is a structured and systematic technique for system examination and risk management. In particular, Hazop is often used as a technique for identifying potential hazards in a system and identifying operability problems likely to lead to nonconforming products. Hazop is based on a theory that assumes risk events are caused by deviations from design or operating intentions. Identification of such deviations is facilitated by using sets of ‘guide words’ as a systematic list of deviation perspectives. This approach is a unique feature of the Hazop methodology that helps stimulate the imagination of team members when exploring potential deviations.

As a risk assessment tool, Hazop is often described as the following.

A brainstorming technique.
A qualitative risk assessment tool.
An inductive risk assessment tool, meaning that it is a ‘bottom-up’ risk identification approach, where success relies on the ability of subject matter experts to predict deviations based on past experiences and general subject matter expertise.

Advantages of Hazop technique are as follows.

Helpful when confronting hazards that are difficult to quantify
Hazards rooted in human performance and behaviors
Hazards that are difficult to detect, analyze, isolate, count, predict, etc.
Methodology doesn’t force any one to explicitly rate or measure deviation probability of occurrence, severity of impact, or ability to detect
Built-in brainstorming methodology
Systematic and comprehensive methodology
More simple and intuitive than other commonly used risk management tools

HAZOP Studies / HIRA / QRA