That poster is the Bow Tie model - one of the clearest ways we visualize risk in HSE.

 That poster is the Bow Tie model - one of the clearest ways we visualize risk in HSE.

Think of it as a bow tie lying on its side. The knot in the middle is the bad thing you don't want to happen. Left side is how you stop it from happening. Right side is how you reduce the damage if it does happen.

The shape

TOP EVENT in the center: The hazardous incident you are controlling. Example: gas release, fall from height, dropped object, loss of containment. Everything else connects to this.

Left side - THREATS & CAUSES: What could make the top event happen.

The poster lists 5 typical ones:

Equipment failure: pump fails, sling snaps

Human error: wrong valve opened, skipped step

Environmental conditions: heavy rain, high wind, poor visibility

External factors: third-party damage, power outage, sabotage

System or process weaknesses: bad design, unclear procedure

Left side barrier - Preventive Barriers: These sit between the threat and the top event. Their job is to keep the threat from becoming an incident.

On the poster:

Procedures: PTW, JSA, SOPs

Training & competence: certified operators, toolbox talks

Engineering controls: guards, interlocks, pressure relief valves

Maintenance: inspections, PM, testing

Supervision: spot checks, oversight

If those fail, the top event occurs. That's when the right side kicks in.

Right side barrier - Mitigating Barriers: These don't prevent the incident, they limit the impact after it happens.

Emergency response plan

Detection & alarms

Fire protection systems

Rescue & medical support

Business continuity: recovery, backup systems

Right side - CONSEQUENCES: What happens if all mitigation fails or is weak:

Injury or loss of life

Environmental damage

Financial loss

Equipment / asset damage

Reputation damage

Regulatory non-compliance

The yellow note says it best: Same event. Two sides. One goal - No harm. STOP THE CAUSES. BLOCK THE EVENT. REDUCE THE IMPACT.

How you build one in practice

This is the HOW IT WORKS bottom section:

List the hazards and possible causes on the left

Identify what preventive barriers you already have, and what you still need

Define the top event very clearly - not too broad, not too vague

Identify recovery / mitigating barriers on the right

List the potential consequences

Use the diagram to find gaps. Where is a barrier missing, degraded, or only on paper?

Why we love it in HSE

It shows the full picture of a risk on one page, which is perfect for risk assessments and toolbox talks

It makes barrier weaknesses visible - you can see if you have 5 preventive controls but zero mitigation

It helps you decide where to spend money and attention

It improves preparedness, because everyone understands their role on the left or right side

It directly reduces likelihood and impact

The bottom line on the poster sums up the philosophy: STRONGER BARRIERS = SAFER PEOPLE + SAFER WORKPLACES + A MORE SUSTAINABLE FUTURE

If you use it for a daily activity, try this quick check for each barrier: Is it effective? Is it actually available right now? Is someone responsible for it? If the answer is no to any, that's your gap to close. 🚧🚥🏗️🚨🗼🌡️⛑️🦺🚦⚠️