Hazard and Operability Study
HAZOP is a structured hazard identification tool using a multi-disciplined team. It has become accepted as the main technique fo r the identification of process hazards in the design and operation of a facility.
Overview and Purpose of HAZOP
HAZOP (Hazard and Operability Study) is a structured hazard identification technique carried out by a multi-disciplinary team. It is widely accepted as the primary method for identifying process hazards in the design and operation of industrial facilities. Unlike discipline-based reviews or checklist approaches—which depend heavily on prior experience and may be limited in scope—HAZOP uses a systematic brainstorming method that provides broader and more thorough hazard identification.
The technique is suitable for a wide range of applications, including major greenfield developments, brownfield projects, small plant modifications, and operating procedures. The core concept involves dividing the plant into manageable sections (nodes) and identifying hazards by applying specific parameters and guide words to structure the brainstorming process.
The objective of a HAZOP study is to identify hazards that could lead to:
- Injury to personnel
- Environmental pollution
- Damage to equipment or structures
- Significant operational disruption
Identified risks are then controlled and minimized through appropriate physical safeguards or operational measures.
HAZOP Study Process Steps
The HAZOP process can be broken down into the following structured steps:
Select the appropriate section of the plant (node).
Define the node’s design intent and process conditions.
Apply the first (or next) process parameter.
Apply the first (or next) guide word to generate a deviation.
Brainstorm and determine all potential causes of the deviation.
Evaluate and agree on the credibility of each cause.
Assess the consequences of each credible cause.
Review the existing protections against the causes and consequences.
Agree on recommendations for action or further study.
Apply the next relevant guide word for the selected parameter.
Apply the next parameter until all have been considered.
Move to the next node and repeat the process until the entire system has been examined.
This structured approach ensures comprehensive hazard identification and systematic risk reduction across the entire facility.