Blood alcohol level: what does it mean and how does the police measure your blood alcohol level?
The blood alcohol level is the number of milligrams of alcohol per milliliter of blood: 0.5 per mille means 0.5 milligrams of alcohol per milliliter. In practice, the police usually measure your breath, not your blood, in micrograms per liter of exhaled air; for this, Article 8 of the Road Traffic Act 1994 establishes separate limits, such as 220 µg/l alongside 0.5 per mille.
The limit that applies to you depends on your driving experience and what else you have used. Below, we explain what the numbers mean, how the police measure, and where a measurement can be vulnerable.
What exactly does per mille mean?
Per mille means “per thousand”. In traffic law, it refers to milligrams of alcohol per milliliter of blood, such as Article 8, paragraph 2, sub b of the Road Traffic Act 1994 it formulates.
A blood alcohol level of 0.5 per mille therefore means 0.5 milligrams of alcohol in every milliliter of blood. How many glasses that amounts to varies per person. The Public Prosecution Service points out that for novice drivers, just one glass can be enough to exceed the 0.2 per mille limit.
What is the difference between breath alcohol and blood alcohol?
Breath alcohol is measured in micrograms of alcohol per liter of exhaled air (µg/l), while blood alcohol is measured in per mille. The law specifies a separate limit for both, and the police record the breath value in the official report.
The boundaries in the law and in the rules of the Public Prosecution Service and the CBR always belong together as a pair. These are the most important:
| Breath alcohol | Blood alcohol | Meaning |
|---|---|---|
| 88 µg/l | 0.2 per mille | limit for novice drivers (Article 8, paragraph 3 of the Road Traffic Act 1994) |
| 220 µg/l | 0.5 per mille | limit for experienced drivers (Article 8, paragraph 2 of the Road Traffic Act 1994) |
| 350 µg/l | 0.8 per mille | driving license confiscation for novice drivers; LEMA for experienced drivers |
| 435 µg/l | 1.0 per mille | EMA for experienced directors |
| 570 µg/l | 1.3 per mille | confiscation of driver's license for experienced drivers |
| 785 µg/l | 1.8 per mille | research into suitability among experienced drivers |
A breath value therefore cannot be converted into per mille using a fixed calculation that applies to every case. For the criminal case, the value established according to the statutory procedure applies.
Which boundaries apply to whom?
For most drivers, the limit is 220 µg/l or 0.5 per mille. A lower limit of 88 µg/l or 0.2 per mille applies to novice drivers and to those who drive a motor vehicle without ever having been issued a driving licence (Article 8, paragraphs 3 and 4 of the Road Traffic Act 1994).
- Experienced driver of car, motorcycle or moped: 220 µg/l or 0.5 per mille.
- Novice driver: 88 µg/l or 0.2 per mille, for five years after the first driving licence, or seven years if you obtained your first AM or T driving licence before the age of eighteen.
- Cyclist: 220 µg/l or 0.5 per mille, because the lower limit only applies to motor vehicles for which a driving licence is required.
- Alcohol in combination with drugs: according to Article 3, paragraph 2 of the Decree on Alcohol, Drugs and Medicines in Traffic, an alcohol limit of 0.2 per mille applies, even for experienced drivers.
You can read more about the lower limit in our article about novice drivers and alcohol.
How does the police measure your blood alcohol level?
The measurement proceeds in steps: first a roadside breathalyzer test, followed by a breath analysis or blood test if necessary. You are obliged to cooperate with every step (Article 160, paragraph 5 and Article 163 of the Road Traffic Act 1994).
- Preliminary breath test: the well-known roadside breathalyzer. This test is a selection tool; the result is not the measurement on which the penalty is based.
- Breath analysis: if the breath test indicates excessive alcohol, a breath analysis using a special device follows, often at the station or in a mobile testing unit. You blow into the device four times if necessary until two usable results are obtained. The analysis may not begin earlier than twenty minutes after the request to take the breath test or the first contact (Article 10 of the Decree on Alcohol, Drugs and Medicines in Traffic).
- Blood test: blood is drawn if a breath analysis is not possible or medically inadvisable, or if there is a suspicion of drug use in addition to alcohol. A doctor or nurse draws the blood.
If you refuse to cooperate, this is punishable under Article 163 of the Road Traffic Act 1994. You can read exactly what your obligations are at obligations and cooperationThe powers of the police during checks are set out in our article about surveillance and investigation.
Can you have a counter-investigation conducted?
Yes. After a breath analysis, you are informed of your right to a counter-examination via a blood sample, which you pay for yourself in advance (Article 11 of the Decree on Alcohol, Drugs and Medicines in Traffic).
You may also have a counter-examination performed after a blood test, at your own expense. If the counter-examination does not confirm the suspicion, you will receive a refund (Article 19 of the same decree). Please note the deadlines: if you do not pay on time, the right to a counter-examination lapses.
How fast does your blood alcohol level drop?
The body breaks down alcohol at a fairly constant rate. According to the Trimbos Institute, this is between 0.1 and 0.25 per mille per hour, and the liver needs about an hour and a half on average for one standard glass.
The variation is wide, and how high your blood alcohol level becomes after drinking also depends on food, drinking speed, body build, and gender. Sleeping does not accelerate breakdown. Therefore, a rule of thumb or online calculator does not provide certainty as to whether you will be below the limit the next morning. Anyone who drank heavily the night before may still blow above 220 µg/l during a morning test.
Can a measurement be incorrect?
A measurement is only valid if the legal procedure has been followed. The Decree on Alcohol, Drugs and Medicines in Traffic and the associated regulations contain precise requirements for this, such as the waiting period of twenty minutes and the use of a designated device.
In general, in an alcohol case, we assess, among other things:
- or the waiting time before the breath analysis has been observed;
- whether there are two valid measurement results and whether the device is designated and approved;
- or you have been informed of your right to a counter-examination;
- whether the claim for cooperation was lawful;
- whether the official report corresponds to what actually happened.
An error in the proceedings does not automatically lead to acquittal. The judge assesses the consequences of a procedural error (Article 359a of the Code of Criminal Procedure). It is therefore important to have the documents reviewed early.
What can we do for you in the event of a disputed measurement?
- We are requesting the full official report and the measurement data.
- We assess the breath analysis or blood test against the Decree and the Regulation.
- We assess whether a counter-investigation is worthwhile and whether the time limit is still running.
- If necessary, we will present our defense before the Public Prosecutor or the police judge.
- We will explain to you which penalty and CBR measure apply to your measurement.
Summary
- Per mille is milligrams of alcohol per milliliter of blood; the police usually measure breath alcohol in µg/l.
- The limit is 220 µg/l or 0.5 per mille; for beginners and in combination with drugs, 0.2 per mille.
- The measurement is carried out via a breath test, breath analysis, and, if necessary, blood test (Articles 160 and 163 of the Road Traffic Act 1994).
- The breakdown varies per person, between 0.1 and 0.25 per mille per hour; a calculation aid provides no certainty.
- A measurement is vulnerable if the legal procedure has not been followed.
Frequently Asked Questions
How many glasses can I drink before driving?
There is no reliable figure for this, because absorption and breakdown vary per person and per situation. According to the Public Prosecution Service, as a novice driver, you can exceed 0.2 per mille with just one glass.
Does the result of the roadside breathalyzer test count?
No. The preliminary breath test is a selection tool. The penalty is based on the breath analysis or the blood test pursuant to Article 163 of the Road Traffic Act 1994.
Can I ask for a blood test myself instead of blowing into a breathalyzer?
The Decree does not mention a personal preference as grounds for a blood test. You are, however, entitled to a counter-examination via a blood sample taken after the breath analysis, at your own expense.
Where can I read more about the penalties?
The penalty per measurement is stated in our article about driving under the influence, based on Public Prosecution Service guideline 2019R013.
Questions about your case?
Email us a few sentences explaining what your question is about, via info@lawandmore.nlWe will let you know if we can help you and what the next step is.
This article provides general information and does not replace advice regarding your specific situation.
