Skip to content

Your Blood Alcohol Limit

Your Blood Alcohol Limit

In most provinces, criminal charges result if you are drinking and driving while over .08. In many provinces there are other sanctions even if you are below .08.

Estimating your blood alcohol level is not easy. Merchant Law cannot warrant these indicators but it will give you some guidance on driver safety.

Your blood alcohol level depends on your weight, the duration of drinking, the amount that you drank, your level of hydration, and is also impacted by whether you drank on an empty or full stomach.

Weight
Your blood alcohol level depends upon your body weight because for every pound over your ideal weight, you carry an additional mile of capillaries. This creates an additional amount of blood to dilute the alcohol. The average heart circulates all of your blood throughout your body every minute. Elite athletes at the top of their heart rate are circulating their blood in the range of 4 or 4.5 times a minute.

Hydration
Water in your system, just like blood in your system, impacts your blood alcohol level. An ounce of alcohol in a litre of blood means a lower blood alcohol level than an ounce of alcohol in two litres of blood. You also have water in your system. If you have been drinking a lot of water, if you are well hydrated, the alcohol will have a lesser affect and your blood alcohol level will be lower.

Stomach Contents
Drinking on a full or empty stomach affects your blood alcohol level. You know this from personal experience. You get a more significant hit from a drink when you have not been eating than when you have been eating. This is caused by two affects. First, alcohol primarily enters your blood through the lower intestine. If your stomach is filled with food the alcohol does not quickly get to the lower intestine. If your stomach has no food, the alcohol, a liquid, will go quickly through your stomach and start to be processed by your lower intestine. Second, the stomach processes alcohol. When the stomach processes the alcohol it does not affect your blood alcohol level. Think of the alcohol being burned by the digestive juices in the stomach. Cumulatively, these two affects are, that if the alcohol is delayed in getting to the lower intestine and burned by the digestive juices in your stomach, drinking on a full stomach will result in a lower blood alcohol level than drinking on an empty stomach. Indeed, in some tests the blood alcohol level is double in the test subjects drinking on an empty stomach as opposed to drinking on a full stomach.

Your liver will dissipate about one ounce of alcohol per hour but the lining of the stomach has an enzyme by which it will dissipate alcohol and assist the liver. Drinking on a full stomach not only slows the impact of the alcohol but your stomach will process and dissipate alcohol even before it gets into your blood and before your liver has to bat clean up. But generally, do not rely on the fact of eating before drinking to be particularly relevant. You may not feel the impact of the alcohol as significantly but it is still in your blood and will show up in tests by authorities.

Duration
Your blood alcohol level depends upon the duration of your drinking because your body processes the alcohol as it is ingested. The alcohol is almost fully absorbed and reaches its peak level in your blood and the impact upon you, about 45 minutes after consumption if drinking on an empty stomach. After consumption, some of the alcohol is taken into your blood stream almost immediately and your blood alcohol level will rise over a 45 minute period from that consumption. Drinking quickly will result in a higher blood alcohol level more quickly but how you feel can be deceptive. Drinking a lot of alcohol slowly may make you feel as though you are not very high and make you feel as though you are not over .08 but you may be. This is because your body over many hours may develop a resistance to the feeling of being impaired and certainly people who drink significantly have a higher tolerance for alcohol and do not sense their high blood alcohol levels.

Age and Ethnicity do not matter!
16 years old, 66 years old, fat, skinny, Nordic, First Nations, lumberjack, candlestick maker, none of these things matter.

Sex Matters!
As a woman, I can drink as much as a man. Not true! It takes less alcohol for a woman to become intoxicated because women process alcohol differently than men. Women reach a higher blood alcohol level than men do after drinking the same amount, even if they are the same height and weight.

Switching Among Beer, Wine, or Spirits, will affect me more
Blood alcohol concentration is what counts – not the type of alcohol you drink. Staying on one type of alcohol or switching among them makes no difference. A drink is a drink. You do not get drunker when you drink hard liquor for example and people who say I stick to beer or wine are becoming just as inebriated. There is the same amount of alcohol in one standard 355 ml can of beer, one standard 142 ml glass of wine, and one standard 43 ml shot of spirits.

Get Energy and Sobering Up
Alcohol does not give you energy. The opposite is true. Alcohol is a depressant and slows down the ability to think, speak, and move. Perception, coordination, and judgment are affected before people begin to notice physical signs of impairment. “Sober up” with a cold shower and a cup of coffee only works in the movies. They feel clean and awake but time is the only thing that will sober you up. Coffee or Red Bull may keep you awake but caffeine will not make you sober.

Estimating
Almost all hard liquor sold in Canada is 80 proof, meaning it is 40% alcohol.

Beer is not so easily categorized. Most Canadian beers are between 4% and 7% alcohol. For the following example, 6% has been used for beer.

Wines, not ice wines or fortified wines which are higher, but ordinary wines are between 11% and 13% alcohol and 12% has been used for this example.

To equally compare a bottle of beer, 12 ounces, a glass of wine, or a drink of spirits:

beer – 12 ounces x 6% = .72 ounces of alcohol
wine – 6 ounces x 12% = .72 ounces of alcohol
spirits – 1.8 ounces x 40% = .72 ounces of alcohol

Many bars serve 1 ounce drinks, some 1.25 ounce drinks, and some, but rarely, 1.5 ounce drinks. 1.8 ounces was selected for the example so there would be a parallel to a bottle of beer. Putting this differently, if your friend is drinking mixed drinks and you are matching him or her by drinking a bottle of beer for every fixed drink, probably a 1 ounce drink, you are probably consuming 80% more alcohol than the person drinking mixed drinks or sipping shots.

The following estimates are based on a man drinking on an empty stomach with normal hydration.
• Suppose you weigh 133 pounds.

• Suppose it is a half hour since you started to drink;

• If in total this person has consumed 1.5 ounces of spirits, or 5 ounces of wine, or 5/6ths of a bottle of beer and it has been a half hour since consuming the drink, he is at about 0.02633%: one drink – .03

• If in total this person has consumed 3 ounces of spirits, or 10 ounces of wine, or about 20 ounces of beer, all within a half hour, he is at about 0.06016%: two drinks – .06

• If the person has consumed 4.5 ounces of spirits, or 15 ounces of wine, or 30 ounces of beer, two and a half bottles, all within a half hour, he is at about 0.0940%: three drinks – .09

If it has been at least an hour and a quarter since you started to drink, probably you will be below .08 but even at 3 drinks, you are close to the line. Your liver will process about one ounce of alcohol per hour.

What to do practically if arrested for drinking
If you think you are close to .08, and not much over, vomiting might help. If you were drinking on an empty stomach, the alcohol will all have passed to your lower intestine. If drinking on a full stomach, you might marginally impact your ascending alcohol by clearing your stomach but this is not a very practical solution and it is unlikely to have much impact. Exercising furiously in your prison cell, burning the alcohol might also marginally help. These ideas might move you from .09 to .087 (and you are always rounded down), but really there is nothing you can do in a practical sense if stopped by the police and taken into custody for the purpose of demanding that you blow.

What should you legally do
Answer no questions. You are not required to answer questions. If they ask if you were driving, refuse to answer. You may think it is obvious that you were driving but do not answer. Ask to speak with a lawyer. Give your name and your driver’s license but no other information. If they ask your address, do not answer. If they ask what your sex is, do not answer. Answering any questions just leads to more questions being asked. By the very fact that you have been arrested, you are not thinking clearly and you are not going to outsmart a member of the police force who is trained to manipulate you and have experience in this process. Call 1-800-lawyers. 1-800-lawyers is 1-800-529-9377. You will reach the closest Merchant Law office in Canada. After hours you likely will reach a telephone answering service but impress upon them the importance of finding a lawyer. Tony Merchant answers telephones at 2 o’clock in the morning. So do our other lawyers. Our advice will be not to say anything and to blow. We may be able to assist in contacting family members if requested.

In some jurisdictions, at only .04 blood alcohol, vehicles are seized, licenses are taken, and fines are imposed. The “.04 law” is a big leap from 50 years ago when breathalyzers became common. For about a decade, in those days, if a person were over .15 that was viewed as evidence that might assist a judge in concluding that the driver was impaired. People over .15 were acquitted from time to time of impaired driving. The .04 law is a big leap from .15 only being corroborative of impairment.

Blow
Do not think you can pretend to blow. Blow as they instruct. It is easier for Merchant Law lawyers to successfully defend being over .08 than a refusal to blow. Merchant Law successfully defends about 50% of the people we represent who are charged with drinking and driving offences.

Alcohol and health
Your liver processes alcohol. Your liver cleanses – processes – most of the bad we consume. We think of big time drinkers risking liver damage. But we can all be impacted and people should ask their doctors for a liver scan to measure the stiffness of the liver. You want a number under 5. Over 7.5 demonstrates danger. Get tested for gamma-glutamyl transferase (GGT) which is rarely authorized for testing in Canada, but you can tell your doctor to put GGT on your liver panel test list.

Health affect is impacted not just by the volume of alcohol you drink but the concentration of alcohol in your blood – the spikes. Two people of equal weight might be different in how high or inebriated they feel and those two people could have significantly different blood alcohol readings. There is much more water in the muscle than fat so people of equal weight will have different diluting effect from the water in their bodies. Weight and the kind of weight impact blood alcohol levels and the sense of being high.

The average O-line starter in the NFL weighs 315 pounds: Trenton Brown of the 49rs weighs in at 355, Donovan Smith of the Buchaneers at 353, Cordy Glenn with the Buffalo Bills weighs 345. That is a great many extra miles in their capillaries, about a mile a pound carrying blood, and a great deal of extra water in their pounds of muscle. But you do not get an enlarged liver with an enlarged neck. If you and your buddy both weigh 220, he is ripped and can press 150, you are dimpled and can barely press a hamburger, he will be able to drink more than you with less effect because his muscle gives him much more water. That may simply lull your muscle buddy into punishing his liver all the more. Muscles, your heart, even eye muscles, probably your brain, get stronger with regular strenuous use but not livers. However, the good thing is that livers can rebound and repair themselves if the damage is caught in appropriate time.

Consumption levels
Availability of alcohol may affect consumption rates although variables are many. Quebeckers drank 144 litres of alcoholic beverages per person of drinking age in the most recent comparable year. This was the highest of any province. Albertans were close behind at 134 litres per adult. In 3rd, Newfoundland Labrador came in at 132 litres. Saskatchewan rates 8th in alcohol consumption. And interestingly the largely urban Ontario, ranks 9th. The people of New Brunswick consumed the least alcohol at 102 litres per person. New Brunswick, a province like Quebec, is Francophone but curiously is 10th, and Quebec is 1st.

The Forgoing is Not Legal Advice.
The information is believed to be accurate but reliance leading to a charge of being over .08 will neither provide a defence to the charges nor grounds to advance a claim against Merchant Law. For specific advice, and in particular specific advice if charged with a drinking and driving offence, call our offices for free initial advice. Merchant Law lawyers have a defence success rate of about 50% but this does not mean we will be successful or unsuccessful in your specific case. Alcohol level readings are often successfully defended. Ask and we may be of assistance.

http://www.alcoholhelpcenter.net/program/bac_standalone.aspx

The foregoing information was prepared by E.F. Anthony Merchant, Q.C. for the assistance of members of the public accessing the Merchant Law website.

About Donald I.M. Outerbridge

Donald became the Executive Director of Merchant Law Group LLP starting in 1993, nearly 30 years ago. His experience managing law firms at various levels and in multiple provinces across Canada goes back even further to 1981.

Please note: The information provided on this website is Not Legal Advice. The information may or may not be accurate. The information is for discussion purposes only. Reliance upon any information provided would not be grounds to advance a claim against Merchant Law for providing any advice. In order to get a formal legal opinion upon which you may rely about any specific fact scenario, you would have to first retain the services of a lawyer and request a formal legal opinion.