Major Accident Hazards and critical safety issues are inherent in the processes involved in refining, mining, chemical and other primary —particularly if those processes don’t work as planned.

Process safety risk can multiply across each process within a facility and across every facility within a large national or multinational corporation, and even one small incident can lead to a more serious risk pathway developing as well. That’s why insurance companies, licensing authorities and government agencies, like the U.S. Occupational Safety and Health Administration and the European Agency for Safety and Health at Work, require Process Hazard Analysis (PHA) to identify, reduce and manage workplace hazards. One common method for PHAs is a Hazard and Operability study, better known as a HAZOP.

What Is a HAZOP?

A HAZOP is a systematic assessment tool used 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. 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. Like all PHAs, HAZOPs go beyond the review of how a process is supposed to operate in order to identify unintended outcomes and explore their potential ripple effects on health and safety.

How to Perform a HAZOP Study

HAZOP studies are performed when new facilities are built, when new processes are introduced or changes are made. They are also used  to look at existing operation and maintenance processes. Typically businesses will assemble a small team of internal experts to conduct the HAZOP and then bring in an outside consultant to help facilitate the study. Teams are selected based on their knowledge of the HAZOP method and/or knowledge of the design, operation, engineering, maintenance or Safety of the process being studied. Often, companies may also choose to add an engineer who is unfamiliar with the process to provide an external point of view.

Once assembled, the team will complete the study in four phases:

  1. Define the scope of the study.
  2. Prepare and collect necessary data (process safety information).
  3. Examine the process and, using potential deviations, brainstorm causes of hazardous scenarios and their possible consequences to determine if they are significant.
  4. Document findings, make safety improvement recommendations and record any changes necessary to reduce risk.

The HAZOP method involves breaking down the process into small, manageable sections called “nodes.” The HAZOP study team will examine the process one node at a time, brainstorming potential scenarios that deviate from the original process design. The team will then define what might cause such a scenario as well as the consequences of the scenario and associated risk. The team will also identify what, if any, mitigating controls may already be in place to help manage and reduce the potential risk. After that, the team will outline specific recommendations to reduce the likelihood of the deviation or reduce associated risks and assign responsibility for carrying out those recommendations. The team will repeat this process until all possible deviations have been exhausted before moving onto the next node.

HAZOP Software

Each scenario identified during the HAZOP study should be documented on worksheets so they can be reviewed, checked and referenced throughout the study and afterward for quality control. Documentation is also essential to stay compliant with regulators and insurance companies. Because of the complexity of the HAZOP method, the complexity of most processes reviewed, and the sheer volume of information that must be consulted, most organizations turn to software to ease the documentation process, such as Sphera’s Process Hazard Analysis (PHA Pro) & HAZOP Software.

Software offers businesses a framework to standardize risk assessment data, record scenarios and ensure recommendations are followed through. Centralized data storage also helps streamline assessments by allowing teams to easily access and build on previous work. The result is a more efficient process with less operational disruption and reduced likelihood of safety incidents.

Further Resources on HAZOP

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