This model is for illustrative purposes. The calculation is based on one unit of alcohol being processed in one hour (source: NHS). The calculation does not take account of numerous factors that influence the processing of alcohol by the body such as an individuals weight, age, height, the length of time drinking, impact of other drinks and whether alcohol is being digested with food. The effect alcohol has on the brain also varies with individual, so everyone's experience is different.
The following research paper provides a wonderful insight into how alcohol is metabolised, what influences it etc, from the perspective of providing a view for judicial purposes.
Law enforcement uses 3 detection methods: breathe, urine and blood to establish an individuals alcohol levels and depending on where in the cycle an assessment is made will generate different results - which highlights how difficult it is to measure exactly. Although based on larger population studies estimates are getting better and the NHS assessment is reasonable.
In summary: Don't rely on this calculator to judge how sober you are, or whether you are fit to drive. It has been generated and published purely for educational purposes. Enjoy.
| Drink Brand | Volume (ml) | ABV (%) | Time | Units of Alcohol | Processed Time |
|---|
Alcohol impairs the brain’s ability to process information, slowing reaction times. Although legal alcohol limits exist in the UK, individuals may be unfit to drive even below these thresholds.
| Test | England, Wales, Northern Ireland | Scotland |
|---|---|---|
| Breath: | 35 micrograms per 100ml | 22 micrograms per 100ml |
| Blood: | 80mg per 100ml | 50mg per 100ml |
| Urine: | 107mg per 100ml | 67mg per 100ml |
1 unit = 8g or 10ml of pure alcohol.
On average, adults metabolize one unit per hour. Variables like weight, metabolism, and stress affect alcohol absorption rates.
Examples of Alcohol Units
- A 4% lager (pint): 2.3 unitsAlcohol continues to affect the body for hours. Waiting 12-24 hours after heavy drinking is advised.
Drinking the night before can still leave you over the limit in the morning. Sleeping, coffee, or showers don't accelerate alcohol breakdown.
Breathalyser Use
- Consider using a breathalyser for certainty, but be aware that alcohol absorption varies.
Preventing Drink Driving
- Use public transport, save taxi numbers, or designate a driver. If in doubt, don't drive.
Consequences of Drink Driving
- Failing or refusing a breathalyser test can lead to arrest, fines, imprisonment, or driving bans. Simply being in a car over the limit (e.g., sleeping in it) is also an offence.