BAC Alcohol Monitoring Tests in Canada (2026 UPDATE)

What Changed for the BAC Tests in Canada in 2026?

Since this article was initially written in 2019, 7 years have passed already. BAC alcohol monitoring test devices have evolved significantly, along with the impaired driving penalties. Some amendments to the Highway Traffic Act have been made, and impaired driving penalties have become even stricter, starting January 1, 2026.

The penalties become harsher for the three main categories:

1. Those caught driving in the “warn” range of a blood-alcohol-content test (0.05 to 0.079 BAC)
2. Those who perform poorly or fail a standard field sobriety test
3. Those who are in the zero-tolerance period of the graduated licensing system (young and novice drivers)

On the first offence, if you fall under one of these 3 categories, your driving licence will be suspended for 7 days, instead of the previous period of 3 days. On your second offence, you’ll lose your driving privileges for two weeks instead of one, plus you’ll have to pay a fine, licence reinstatement fee, and take a remedial education course. Read more on over 80 penalties and how to avoid them on our respective page.

Factors Influencing BAC During Alcohol Monitoring Tests

Blood alcohol concentration (BAC) is a standard measurement that describes how drunk a person may be. Different percentages of alcohol in the blood lead to varying levels of mental and physical changes and risks. In Canada, a BAC of 0.08% is the legal limit, meaning one can no longer safely drive after this point. The percent is related to how many parts alcohol are in the blood; a BAC of 0.1% represents one part alcohol per 1,000 parts blood.

As the liver metabolizes about 1 standard drink per hour, 1 to 2 drinks raise the BAC by a small amount, ranging from 0.01% to 0.05%, depending on factors such as weight, gender, age, and any prescription medications.

Two to three drinks raise BAC to between 0.06% and 0.1%. Memory, judgment, reaction time, perception, and fine motor skills are affected at this point. Higher BACs lead to inappropriate social behaviors, loss of balance, slurred speech, memory loss, blackouts, low body temperature, trouble breathing, vomiting, and even sudden death.

If, after being tested, you’re ever charged with impaired driving, it’s best to seek legal help from a DUI lawyer Mississauga expert who knows the local courts and procedures.

Different BAC Test Options

In Canada, there are various options for testing suspects for impaired driving. Some of them show the exact amount of alcohol one has drunk, while others can only show whether one has consumed alcohol today or not. Police officers during roadside stops usually use a standard field sobriety test, and only if you fail it will you be required to pass blood or urine tests.

Balance Test

The Romberg balance test is often given to determine whether one is intoxicated or not. The Romberg balance test is based on the concept that three functions are necessary to remain standing still: vision, proprioception (the sense of where limbs are in space), and vestibular function (equilibrium provided by the inner ear). Drinking alcohol changes how the inner ear senses the body’s orientation in space and changes how the brain processes visual images. Clues listed by the Romberg test that may indicate drunkenness include:

• Amount and direction of body swaying
• Eyelid or body tremors
• Estimation of time passing
• Muscle tone
• Sounds or phrases during the test, including whether speech is slurred
• Ability to follow directions and how quickly

A police officer who pulls a person over for a suspected DUI may administer this field sobriety test. The officer will ask the suspect to stand still with their feet together, tilt their head back, close their eyes, and estimate how long it takes for 30 seconds to pass.

The Romberg test is not the only balance test, nor is it standardized, but it is one of the more popular.

Breathalyzer Test

A breathalyzer test to determine BAC relies on the body’s metabolism of alcohol to assess the level of alcohol in the blood. About 92-98% of an alcoholic beverage moves through the digestive system to be broken down by the liver, so 2-8 percent is lost through other processes, including breathing. Some alcohol enters the bloodstream through the stomach walls before the liver breaks it down. This alcohol-tinged blood then circulates throughout the body, including the lungs, where some alcohol is exhaled.

The liver processes about one serving of alcohol per hour, so if a person drinks more than one standard drink in an hour, more of that alcohol will enter the bloodstream at this point, circulating through the heart and lungs, so more alcohol will be exhaled. The amount of alcohol collected in the lungs correlates to the amount of undigested alcohol in the bloodstream at a ratio of about 2,100 breaths to 1 blood. So, for example, 2,100 milliliters of alcohol in an exhale correlates to about 1 mL in the blood.

A breathalyzer test can detect alcohol consumption about 24 hours after the person drinks, although it does not measure how high the individual’s BAC may have been in the past. Any remaining alcohol in the lungs will be measured via a chemical reaction in the device, which detects alcohol in the exhale by changing color from reddish-orange to green.

Mandatory Alcohol Screenings (MAS) are happening more and more often in Canada. A police officer can randomly stop you for a breathalyzer test to check whether alcohol is in your blood.

Blood Alcohol Test

Alcohol does not remain in the blood for long, and a blood alcohol test can only detect alcohol in the bloodstream for up to 12 hours after the last drink. It is the preferred test to determine whether a person is drunk at the specific time their blood was drawn. The blood alcohol test is used during DUI arrests or in rehabilitation centers treating people with chronic alcohol use disorder. Other tests, especially the hair test, can show that the person drank alcohol, but not specifically when or how drunk they got.

Urine Test

Because the liver is the main alcohol metabolizer in the body, the digested toxins will filter out of the body, in part, through the kidneys. Urine tests can detect metabolized alcohol between 12 and 48 hours after the person drinks, depending on how much alcohol they drink.

Hair Tests

Very few occasions require a hair test to determine whether a person drank alcohol, but alcohol consumption can be detected for up to 90 days in hair tests.

Conclusion

As Ontario’s government strives to make streets safer, alcohol monitoring tests and impaired driving penalties for their failure will continue to evolve. According to the statistics, some progress has already been made, yet drinking and driving fatal incidents continue to grow and remain a big problem.

We, as well, want to make Canadian roads safer. Thus, if you have been drinking, we advise you not to drive. If there are circumstances that force you to do so, we totally understand. If you have been charged with a DUI, don’t wait. Call Jonathan Lapid, an experienced DUI lawyer, at 647-694-3933.

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