How many pints of beer before you're over the limit?

Question: How many pints of beer would it take to put you over the drink drive limit in the UK?

Alcohol is broken down by the liver at a rate of around 1 pint per hour for men. Factors such as age, weight, gender, and amount of food eaten can affect how fast the body can process alcohol. The rate of alcohol absorption cannot be increased by sleeping, drinking water or sucking a penny (a common myth)! About 10% of alcohol is eliminated through breath, sweat and urine.

The rate at which we eliminate alcohol is important, particularly in the context of a drink driving case. What if your breath reading was much higher than expected? What other factors influence elimination rates? 

A positive breath, blood or urine result does not make you guilty of drink driving. We regularly win cases due to procedural mistakes and legal loopholes. As a general rule, you should always check the evidence.

- Conor Johnstone

For Men -

These calculations assume that you're breath tested one hour after consuming the alcohol. In many cases, a breath test will take place over two hours after consumption

The average UK male is 5ft 9in tall (175cm) and weighs 13 stone (83kg). A pint of beer (3.6%) contains 19.8ml of alcohol. 

How many pints? Breath Reading (one hour after drinking) Under/Over
1 pint consumed within 30 minutes  6 microgrammes Under the limit
2 pints consumed within one hour 13 microgrammes Under the limit
3 pints consumed within two hours 19 microgrammes Under the limit
4 pints consumed within three hours 26 microgrammes Under the limit
5 pints consumed within four hours  32 microgrammes  Under the limit

These results may seem surprising, but remember that alcohol begins to breakdown very quickly. This means that if you consume five pints of beer within 4 hours, the first 2 pints will have been completely eliminated by the time you start your 5th pint. Of course, if you 'knock back' 5 pints very quickly, the level of alcohol in your system will be much higher.

5 steps to take if you're charged with drink driving

  1. Carefully review the police paperwork
    Often the police make silly mistakes on official paperwork. Our recent case study talks about mistakes with police paperwork. 
    CASE STUDY - Missing evidence
  2. Seek free legal advice from a specialist firm
    A specialist firm can advise you on technical points of law and procedure. You can read more about technical defences here.
  3. Consider your options 
    Do you know what a 'basis of plea' is? Do you know what to include in mitigation? Can you plead not guilty?  
  4. Consider any available defences
    You may have a defence without realising. Even if you can't defend the case, you may have a special reason to avoid a ban
  5. Check the evidence against you
    How will know if the evidence is correct if you haven't seen it? 
    Why you should check the evidence

Remember - Don't just plead guilty. You may have a defence to the allegation without knowing. Every drink driving case we have ever won in court starts with a breath reading above the prescribed limit. 

How Long Does Alcohol Stay in Your System?

Depending on the body system and test used, alcohol detection times may vary. Alcohol detection tests used by police forces can measure alcohol in the breath for 12 to 24 hours. If you want to know more about breath test machine, you can read our drink driving breath page. The table below contains some standard rules of alcohol elimination. 

Body System Time in System
Blood Up to 6 Hours
Breath 12-24 Hours
Urine 12-24 Hours
Saliva (not used by police) 12-24 Hours
Hair (not used by police) Up to 90 Days

If you're stopped and arrested on suspicion of drink driving, you are likely to be breath tested. The legal limit for alcohol in the UK is 35 microgrammes (ug). However, the police do not prosecute until 40ug to allow for unreliable readings or over-estimations. 

An evidential breath test machine has to be correctly maintained by the police. This means regular servicing and recalibration. Often, due to miscommunication and poor training, the police fail to correctly maintain breath machines. Remember that you can always ask the police to provide calibration data (this includes maintenance logs and service records). 

To read more about Type Approval Orders in the UK, click here

Drink Driving Ban Calculator 

Step 1 of 3

Have you been convicted of drink driving within the last 10 years?

Step 2 of 3

What type of sample did you provide?

Step 3 of 3

What was the level reading for ?

How to speed up alcohol metabolism

Unfortunately, there is practical way to speed up alcohol metabolism. If you eat before drinking alcohol you will metabolise alcohol quicker than on an empty stomach. This is because the food in your stomach will help to absorb the alcohol (reducing the amount that enters your blood stream). It is also due to an increased blood flow and increase liver enzymes (which help to break down food and drink). 

However, eating after drinking alcohol is not a fool-proof way of avoiding a drink driving charge. A full stomach will only slightly increase your absorption rate. In addition, once the alcohol has actually entered your blood stream, there is no way of reducing its content. 

Free Legal Advice from M.A.J Law

M.A.J Law are specialist driving defence solicitors. We believe that every motorist has the right to independent legal advice. For this reason, we offer every motorist free specialist advice no matter what your circumstances.

M.A.J Law work on a fixed fee basis, so you don't have to worry about ongoing legal costs as your case progresses. If you would like to know more about your options, please get in touch.

Useful Links 

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