The total distance it takes to bring a car to a stop from the moment a hazard is first seen on the road is known as the stopping distance. This is the sum of the perception, reaction, and braking distances.

Perception Distance

• Definition: The distance the car travels between when the driver sees a hazard and when the brain registers it.
• Factors:
  • Distractions like phone use, changing the radio, or looking away can increase perception time.
  • Influences such as alcohol, drugs, fatigue, and sleepiness can extend perception time up to 4 seconds.
  • At 100 km/h, travelling for 4 seconds means covering 110 meters, longer than a football field.
• Importance: Always attentive to the road is crucial to minimize perception distance.

Reaction Time

• Definition: The time it takes for the driver to react to a hazard and begin an evasive maneuver, such as braking.
• Factors: All factors that affect perception time (distractions, alcohol, drugs, fatigue) also affect reaction time.

Braking Distance

• Definition: The distance the car travels from the time the brakes are applied until the vehicle comes to a complete stop.
• Factors:
  • Speed: Higher speeds increase braking distance. Stopping a 100 km/h vehicle can take up to 170 meters.
  • Road Conditions: Wet, icy, or snowy roads increase braking distance. Drivers should increase following distance and reduce speed in these conditions.
  • Vehicle Condition: Well-maintained brakes, tires, and other components are essential for safe braking.

Calculating Stopping Distance

To calculate the stopping distance, use the following formula:$\text{Total stopping distance} = \text{Thinking distance} + \text{Braking distance}$

• Total Stopping Distance = Thinking distance + Braking distance
• Thinking Distance: The distance the vehicle travels while the driver recognizes the need to stop and applies the brakes. This is usually between 1 and 1.5 seconds, depending on reaction time.
• Braking Distance: Braking distance is the distance the vehicle travels while the brakes are applied. It depends on the vehicle’s speed, weight, braking system, and road conditions.

Guidelines for Safe Driving

• Maintain a Safe Following Distance: Leave at least two seconds between your vehicle and the vehicle in front of you. Increase this distance in adverse conditions.
• Stay Attentive: Avoid distractions and stay focused on the road to minimize perception and reaction times.
• Adapt to Conditions: Reduce speed and increase following distance on wet, icy, or snowy roads.
• Regular Maintenance: Ensure your vehicle’s brakes, tires, and other components are in good condition through regular maintenance and inspections.

Conclusion

Understanding and managing stopping distances are crucial for safe and responsible driving in Ontario. By staying aware of the factors that affect stopping distance and taking proactive steps, drivers can help prevent accidents and promote road safety.