Safety and law
Drink Driving Penalty and Rules Every Singapore Learner Should Know
A safety guide to alcohol limits, drink-driving penalty cues, impairment, test traps, and the practical rule learners should use: if you drink, do not drive.
Last reviewed: 1 June 2026. Handbook baseline: 58.
35ug
per 100ml breath
80mg
per 100ml blood
Safer rule
If you drink, do not drive.
Remember
The handbook states legal alcohol limits as 35ug per 100ml breath or 80mg per 100ml blood.
Remember
Alcohol reduces judgement, concentration, coordination, and reaction time.
Remember
The safe learner rule is simpler than the legal threshold: if you drink, do not drive.
Do not treat the limit as a target
The theory test may ask for exact values, but safe-driving questions usually reward a stricter mindset. The legal threshold is not a personal safety target. Impairment can appear before a learner feels obviously drunk.
Memorise 35ug per 100ml breath.
Memorise 80mg per 100ml blood.
Use a non-driving plan if alcohol is involved.
Impairment is broader than the number
Alcohol affects judgement, concentration, coordination, and reaction time. Those are exactly the abilities needed for hazard perception, lane discipline, braking, and responding to pedestrians or cyclists.
Feeling normal is not proof that driving is safe.
Food, sleep, medication, and body size can affect impairment.
The safest test answer normally avoids driving after drinking.
Below the limit can still be unsafe
The handbook warns that a driver can still face consequences if there is evidence of inability to control the vehicle because of intoxication. That is why the learner rule should be behaviour-based, not only number-based.
Do not drive if alcohol has affected control or judgement.
Do not rely on rough calculations after drinking.
Choose taxi, public transport, a designated driver, or waiting until safe.
How questions usually trap learners
A question may mix exact values with a scenario where the driver feels fine, is close to home, or has driven slowly. Those details do not make drink driving safe. The correct answer normally protects the road user, not convenience.
Ignore convenience-based excuses.
Separate breath and blood units carefully.
Remember that alcohol affects reaction time before a crash happens.
Scenario check
Apply the rule before you move on.
These short checks are intentionally close to how test traps feel: one detail changes the answer.
Question
A learner knows they are below the legal limit and feels fine.
Answer
The safer answer is still to avoid driving after drinking. Impairment can be underestimated.
Question
A question asks for the blood alcohol limit.
Answer
Recall 80mg per 100ml blood. For breath, recall 35ug per 100ml breath.
Question
A driver has been drinking but says the trip is only a short distance.
Answer
Short distance does not remove impairment risk. Do not drive after drinking.
Next step
Turn this guide into active recall.
Read the related module for full explanation, then use flashcards to check whether the distinction is actually memorised.
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