The Crash Reduction Factor (CRF) formula is a widely used metric in Quality, Environment, Health, and Safety (QEHS) and road safety management to evaluate the effectiveness of safety interventions. It quantifies the percentage reduction in crashes after implementing a safety measure, such as speed limits, road redesign, or traffic signals. The formula you provided is correct and aligns with standard practices in road safety analysis.

Understanding Crash Reduction Factor (CRF)

The Crash Reduction Factor (CRF) measures the percentage decrease in crashes after implementing a safety intervention. It is a key metric for evaluating the effectiveness of road safety measures.

Explanation of Parameters:

• Crashes Before Intervention: This represents the total number of crashes recorded before implementing any safety measure. It provides the baseline data for comparison.
• Crashes After Intervention: This indicates the total number of crashes recorded after the safety measure has been applied. It helps in assessing the effectiveness of the intervention.
• Crash Reduction Factor (CRF): The calculated percentage representing the reduction in crashes. A higher CRF suggests a more effective safety measure, while a lower CRF indicates minimal impact.

Purpose of CRF:

• Evaluate Interventions: Assess the impact of safety measures like speed limits, road redesign, or traffic signals.
• Optimize Strategies: Use CRF data to prioritize cost-effective safety improvements.
• Monitor Progress: Track long-term trends in crash reduction.

Practical Insights:

• High CRF: Indicates a successful intervention with significant crash reduction.
• Low CRF: Suggests the need for reevaluating or enhancing the safety measure.
• Data-Driven Decisions: Use CRF to support evidence-based road safety policies.