HAZIDs and HAZOPs
Hazard identification (HAZID), Hazard and Operability Studies (HAZOP) and BowTie analysis are complementary risk management techniques that support different stages of the risk assessment process. While each technique serves a different purpose, together they provide a structured approach to understanding hazards, evaluating controls and managing major accident risks throughout the asset lifecycle.
HAZID
A HAZID is typically performed early in the lifecycle of a project or activity to identify potential hazards, hazardous events and areas of concern. It provides a broad understanding of the risks that need further investigation and helps determine where more detailed analysis is required. HAZIDs are often used during concept design, project planning, or when introducing significant operational changes.
The output from a HAZID is typically a structured list of hazards, hazardous events and recommendations that define the scope for more detailed assessment.
HAZOP
A HAZOP provides the next level of analysis by systematically examining a process or activity using structured guide words to identify deviations from the intended operation, their possible causes and their potential consequences. The HAZOP study records each deviation in detail, identifies existing safeguards and recommends actions to reduce risk where necessary. HAZOPs are particularly valuable because they provide a comprehensive and traceable record of the assessment, ensuring that potential failures have been considered methodically by a multi-disciplinary team.
Many of the safeguards identified during a HAZOP subsequently become preventive or recovery barriers within a BowTie.
BowTie Analysis
BowTie analysis builds upon the information generated during HAZIDs and HAZOPs by presenting the risk in a clear and visual format. Unlike HAZIDs and HAZOPs, which primarily record findings in a dull tabular form, BowTie analysis presents the relationships between hazards, threats, the top event, consequences and the preventive and recovery barriers that control the risk within a single visual model. This visual approach makes complex risk information easier to understand and communicate to a wider audience, including operational personnel, managers, and stakeholders who may not have participated in the original assessment. In practice, the hazards and recommendations identified during a HAZOP often form the basis of the barriers represented within the Bowtie diagram, providing a direct link between the detailed analysis and the ongoing management of critical controls.
Bring everything together with BowTie Pro
BowTie Pro brings these techniques together by enabling organisations to develop, manage and maintain BowTie diagrams to rapidly create an initial BowTie framework by allowing import of information captured during HAZIDs, HAZOPs and other risk assessments which can then be refined and validated through reviews by subject matter experts or facilitated workshops.
BowTie Pro supports this process by:
- importing hazards, threats and recommendations directly from HAZID studies;
- importing HAZOP worksheets to accelerate BowTie development;
- providing industry example files
- using AI-assisted features to help generate an initial BowTie structure.
Once imported, the information can be reviewed and validated to ensure that threats, consequences, barriers and responsibilities accurately reflect the operation being assessed. This collaborative review ensures that the BowTie represents current operational knowledge while maintaining alignment with the original HAZID and HAZOP studies.
By the use of BowTie diagrams, BowTie Pro provides an organisation with a consistent, evidence-based approach to managing critical risks. It improves communication between disciplines, supports the ownership and assurance of critical barriers, enables action tracking and promotes the continual improvement of barrier performance throughout the asset lifecycle.