Humans in traffic – Factors that affect driving

Driving is a human task. Our abilities and limitations shape safety every second behind the wheel. This guide covers key human factors and how to manage them.

Vision and attention

• Scan broadly, focus ahead, and keep eyes moving
• Use mirrors frequently, check blind spots

Reaction time

Affected by expectation, workload, fatigue, alcohol/medicines and distraction. See Reaction time and braking distance .

Distractions

Phones, passengers, infotainment and outside events can steal attention. See Mobile phone distractions .

Alcohol and drugs

Even low doses impair driving. See Alcohol, BAC limit and drugs .

Stress and emotions

High stress narrows attention and increases risk taking. Breathe, slow down, and add buffer time.

Fatigue

Plan breaks, avoid night‑time driving when tired, and stop if drowsy.

Learning and self‑evaluation

Reflect on your habits, seek feedback, and practice deliberately.

Age and ability

Abilities change with age. Adjust exposure and habits accordingly.

Decision‑making and risk

Good decisions rely on seeing hazards early, leaving margins, and avoiding time pressure. See Risk assessment in practice .