0.5‰ and effects on reflexes

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The 0.5 g/l limit in Belgium: how alcohol affects your reflexes, your vision and your reaction time behind the wheel.

Coverage, 0.5‰ and effects on reflexes

Lesson objectives

Understand the legal threshold of 0.22 mg/l of exhaled alveolar air and its immediate consequences Identify how alcohol impairs the driver's reflexes and concentration Know the rules applicable to novice drivers and professional drivers

The legal threshold: 0.22 mg/l of exhaled alveolar air

In Belgium, an ordinary driver is punishable from 0.22 milligrams per litre of exhaled alveolar air (approximately 0.5 g/l of blood ). The concentration must therefore remain below this threshold. As soon as this rate is reached, you commit an offence and expose yourself to immediate sanctions.

The three levels of alcohol rates and their consequences

Alcohol rate (mg/l of exhaled alveolar air) Result Immediate consequences Less than 0.22 Safe (S) No sanctions related to alcohol rate From 0.22 to less than 0.35 Warning (A) 12 hours of temporary driving ban + possible immediate collection of 197 € From 0.35 to less than 0.44 Positive (P) 12 hours of temporary driving ban + possible immediate collection of 462 € (immediate licence withdrawal possible if driving is deemed dangerous) From 0.44 to less than 0.50 Positive (P) 12 hours of temporary driving ban + possible immediate collection of 636 € (immediate licence withdrawal possible if driving is deemed dangerous) 0.50 or more Positive (P) 12 hours of temporary driving ban + immediate licence withdrawal for 15 days + mandatory court appearance (no immediate collection)

Alcohol testing: breath test

Breathalyser

Portable device used by police to detect the presence of alcohol in exhaled alveolar air. In case of a positive result, a breath analysis determines the exact alcohol concentration.

How alcohol affects your reflexes and driving

Alcohol does not only affect your judgment: it slows down your reflexes and impairs your ability to react quickly to dangers. Even at low doses, alcohol:

Reduces your concentration and attention Slows down your reaction time to an obstacle or emergency braking Affects your judgment of distances and speeds Increases your fatigue and drowsiness Causes presumptuous and reckless behaviour

Remember: at 90 km/h , you travel approximately 25 m in one second. If alcohol slows your reaction by half a second, you have already travelled 12.5 m more before you start braking. This extra distance can be fatal.

Reaction distance lengthened by alcohol

Special rules for young drivers

Young drivers who have held their licence for less than two years are subject to enhanced monitoring. The legal threshold remains 0.22 mg/l , but the consequences are more severe: in case of conviction for driving under the influence of alcohol or drugs, the judge must impose a driving ban and make reinstatement conditional on passing examinations. The same applies to other serious offences, such as hit-and-run.

Professional drivers (in particular truck drivers, bus drivers and taxi drivers on duty) are punishable from 0.09 mg/l of exhaled alveolar air (approximately 0.2 g/l of blood ).

Professional driver

A driver subject, in situations provided for by law, to the stricter professional threshold of 0.09 mg/l of exhaled alveolar air, in particular a truck driver, bus driver or taxi driver on duty.

Interaction between alcohol and medication: a doubled danger

Some medications already have harmful effects on driving (drowsiness, slowed reflexes). Mixing alcohol with these medications creates a synergy effect : alcohol amplifies the medication's side effects, making driving extremely dangerous.

Medications that interact with alcohol:

Sleeping pills and hypnotics Anxiolytics (sedatives) Antidepressants Antihistamines (for allergies) Pain relievers

Before driving after taking medication, consult the package insert or your pharmacist. Some sleeping pills taken in the evening may still affect your alertness the next morning. If in doubt, refrain from driving.

What happens during a check?

Police can check the blood alcohol level of any driver : motorist, motorcyclist, cyclist or even rider. If you are suspected or involved in an accident, the test is mandatory.

Who can be checked?

Drivers of motorized vehicles Cyclists Riders Driving school instructors Alleged perpetrator of a traffic accident

Refusing the test or breath analysis results in a temporary driving ban of 12 hours , immediate license withdrawal for 15 days , a settlement offer of 735 € and prosecution before the court. Since May 1, 2024, it is no longer possible to request the 15-minute waiting period before the first test.

Blood test: when and why?

If the breath test is impossible (you are hospitalized, asthmatic, too drunk to blow), police can order a blood test . This test is performed by a doctor, not by a police officer.

Key points to remember

The legal limit in Belgium is set at 0.22 mg/l of expired alveolar air (approximately 0.5 g/l of blood ). Since July 1, 2026 (law of May 25, 2026), from 0.22 mg/l the temporary driving ban is 12 hours for any driver: the old durations of 3 and 6 hours no longer exist. From 0.22 to less than 0.35 mg/l: 12 hours ban + possible immediate fine of 197 €. From 0.35 to less than 0.50 mg/l: 12 hours ban + possible immediate fine (462 € or 636 € depending on the level). From 0.50 mg/l : 12 hours ban, immediate license withdrawal for 15 days and mandatory court appearance. Alcohol slows your reflexes , reduces your concentration and impairs your judgment . Novice drivers and young drivers are subject to the general limit of 0.22 mg/l, but risk mandatory disqualification from driving. A stricter limit of 0.09 mg/l applies to professional drivers. Mixing alcohol and certain medications can produce a dangerous combined effect . Refusing to blow results in 12 hours driving ban, immediate license withdrawal for 15 days and prosecution. Any person driving a vehicle or riding an animal on public roads can be checked: motorists, cyclists, riders.

What now?

First take the quiz of this lesson to validate your learning, then practice on the exam simulator and multiple choice questions . Next lesson: Sanctions, medications and illegal drugs .

BelgianLicenses

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