what is the 4P methodology in workplace risk assessment?

Prediction is where the 4P methodology starts, because everything that follows depends on it. This stage is about understanding the risk people face, not making assumptions based on past practice or generic categories.

In electrical environments, prediction means calculating potential incident energy levels using recognised engineering methods. Engineers model the system using standards such as IEEE 1584, which sets out how arc flash energy is calculated at specific points based on how the equipment is built and protected.

From this, incident energy levels are established and arc flash boundaries defined. These figures tell you how much thermal energy a person could be exposed to, and at what distance. Without this information, decisions about isolation, procedures, or protective clothing are based on assumptions rather than evidence.

Accurate prediction helps you determine where the real dangers are—and just as importantly, where they aren’t. Then the rest of the assessment can focus on protecting people in a targeted, proportionate way.

Once you understand the level of risk, the next step is to stop people being exposed to it in the first place. Prevention focuses on changing the task or the system, so the hazard is removed or reduced before anyone has to rely on what they’re wearing.

The safest option is always dead working. If equipment can be isolated, locked off, and proven safe, the arc flash hazard no longer exists for the person doing the work. Where live work cannot be avoided, prevention is about limiting how severe an incident could be and how long it lasts.

On site, that usually means introducing controls like:

• Automatic Disconnection of Supply (ADS), where protection settings are adjusted so faults clear more quickly and release less energy.
• Equipment designed to manage arc energy, such as arc-resistant switchgear or internal arc control systems.
• Remote operation, using racking devices or switching tools that allow work to be done outside the arc flash boundary.
• Task planning that removes exposure, so people are not positioned in front of live equipment during high-risk operations.

Each of these measures reduces how close people need to be to danger. If you implement prevention properly, you lower the demands placed on procedures and protective clothing later.

Even the best engineering controls only work if people interact with them in the right way. The process pillar focuses on how work is planned, authorised, and carried out, allowing for safe decisions that depend on memory or habit in high-pressure situations.

This stage is about giving your team clear boundaries and support before they approach live equipment. It defines who can do the work, under what conditions, and what must be checked before a task begins.

Strong process controls usually include:

• Clear rules on dead working, so live tasks are the exception, not the norm.
• Permit-to-work systems that confirm isolation, competence, and authorisation before access is granted.
• Safe Systems of Work (SSoW), setting out each step of the task, the tools allowed, and the conditions that must be met.
• On-site checks before work starts, allowing workers to flag changes that weren’t visible during the original assessment.

Process is where the human element is properly accounted for. It recognises that people work in changing environments, and then builds safeguards that support good judgement, rather than assuming perfect behaviour.