Why can vision be affected even at low alcohol levels?
Serve It Right Saskatchewan: Alcohol and impairment
How alcohol affects judgment first and then muscle control, what counts as one drink, why only time lowers blood alcohol, crash risk at different levels and the multiplying effect of alcohol with other drugs.
- No sign-up
- Every answer explained
- Independent · not a government site
- 15 questions
- Topic drill
Study reference: Saskatchewan liquor law and SLGA policy (Oct 2026), Ch. 4 Alcohol and impairment — SGI Driver's Handbook, Alcohol; Drinking and drugs combined; SLGA Responsible Hosting Guide (2026)
All 15 questions in this test
Every question and its answer choices. The correct answers and explanations appear when you take the test above.
Why can vision be affected even at low alcohol levels?
- Alcohol only affects people who wear glasses
- Bar lighting causes the effect, not the alcohol
- Alcohol makes the pupils shrink too much for clear sight at night
- The small muscles of the eye are very sensitive to alcohol
What does SLGA's hosting guide say about coffee and intoxication?
- Coffee works if it is served with dessert
- Coffee works faster than drinking water
- Two strong cups of coffee will sober up most healthy adults
- Coffee cannot overcome the effects of alcohol
Which factor does SGI list as affecting a person's blood alcohol content?
- The brand of glass used for the drink
- The time zone where the bar is located
- The colour of the drink being served
- The amount of food the person has eaten
Compared with a sober driver, how much more likely is a crash at a BAC of .15% or more?
- About 380 times
- About 5 times
- About 48 times
- About 11 times
What is the first thing alcohol affects, starting with the first drink?
- Balance and walking
- Hearing and smell
- Hand strength
- Judgment and decision-making
A patron plans to sleep for three hours and then drive home after heavy drinking. What does SGI say?
- Sleep works if the patron drinks water first
- Three hours of sleep clears any amount of alcohol
- You cannot sleep off heavy drinking in a few hours
- Sleep works if the patron has eaten a large meal
Which serving does SGI count as one drink?
- 3 oz of hard liquor
- 10 oz of table wine
- 5 oz of table wine
- Two bottles of regular beer
About how fast does alcohol leave the body, according to SGI?
- About .15% BAC per hour
- It leaves faster with coffee
- About .05% BAC per hour
- About .015% BAC per hour
What kind of drug is alcohol, according to SGI?
- A harmless food product with no effect on the brain
- A stimulant that speeds up the brain, the heart rate and reflexes
- An addictive drug that depresses the central nervous system
- A drug that sharpens reaction time at low doses
A driver had two drinks and a cold remedy. What will a breath test show?
- Only the alcohol from the two drinks
- Twice the real blood alcohol level
- Nothing, because cold remedies block it
- The full effect of both drugs together
What does SGI mean by the synergistic effect of alcohol and other drugs?
- The two drugs cancel each other out completely
- Only the drug taken first has any effect at all
- The combined impairment is greater than the two added together
- The other drug lowers the blood alcohol reading, so impairment drops
Why does SLGA suggest serving drinks yourself instead of an open bar?
- Open bars make it harder to collect payment
- Guests typically drink more when they serve themselves
- Guests pour too little and complain about it
- Self-service bars are not allowed at private functions held at home
What BAC does SGI call the only truly safe level for driving?
- Under .04%
- Under .05%
- 0%
- Under .08%
Per SGI's example, two drinks plus one marijuana joint impair a person about as much as how many drinks?
- 5 to 6 drinks
- 10 to 12 drinks
- 3 drinks
- 2 drinks
How much fortified wine, such as port or sherry, does SGI count as one drink?
- 8 oz
- 1.5 oz
- 3 oz
- 5 oz
Alcohol and impairment: key rules to remember
Our summary of what the official handbook says on this topic, in our own words. Read it before or after the practice questions above, then check the original chapter. Read the official chapter ↗
Alcohol
- Alcohol is a legal but addictive drug that depresses the central nervous system, affecting mood and behaviour.
- Blood alcohol content (BAC) is affected by age, gender, physical condition, food eaten, medication and other factors; mixed drinks contain different amounts of alcohol, so count the alcohol, not just the number of drinks.
- Alcohol is absorbed into the bloodstream very quickly.
- The first part of the body affected is the brain's judgment and decision-making, starting with the first drink, usually without the drinker noticing; social inhibitions are also reduced.
- Muscle control is affected next; the small eye muscles are very sensitive, so vision can suffer even at low levels.
- Most alcohol-related collisions come from faulty identifying, predicting and deciding, not from poor steering or braking.
- At about .08% BAC: muscle coordination becomes poor (balance, speech, vision, reaction time, hearing), and judgment, self-control, reasoning and memory are impaired.
- Crash likelihood compared with sober driving: about 11 times at .05–.09% BAC, 48 times at .10–.14% and 380 times at .15% or more. The only truly safe BAC is 0%.
- Only time removes alcohol; it leaves the body at roughly .015% per hour, so sleeping a few hours does not sober a heavy drinker up.
Drinking and drugs combined
- One drink = one bottle of regular beer, 5 oz of table wine, 3 oz of fortified wine (port, sherry) or 1.5 oz of hard liquor.
- Alcohol combined with another drug has a synergistic (multiplying) effect, far greater than the two added together.
- SGI examples: 2 drinks + an antihistamine cold remedy ≈ 4 to 5 drinks; 2 drinks + one joint ≈ 5 to 6; 2 drinks + a normal dose of Valium ≈ 6; 2 drinks + Gravol ≈ 6.
- A breath test shows only the alcohol, so the reading understates the real impairment.
effects of alcohol
- Even at low levels, alcohol affects perception, judgment, coordination and decision-making long before obvious signs of impairment appear.
- Coffee cannot overcome the effects of alcohol.
- Guests drink more when they serve themselves; avoid doubles and use a measure to prevent over-pouring.
- Offer high-protein and carbohydrate foods; salty and greasy snacks make guests thirstier.
- Stop serving alcohol at least an hour before the event ends and switch to food and non-alcoholic drinks.
Responsible liquor use
- SLGA supports Canada's Guidance on Alcohol and Health and promotes standard drink sizes with its Size Matters poster.
- Fetal Alcohol Spectrum Disorder (FASD) is caused by alcohol use during pregnancy and can cause lifelong learning, behavioural and cognitive difficulties.
Other topics
- SIRS certification rulesWho must hold Serve It Right Saskatchewan, the before-first-shift rule, owners and corporations, volunteers, five-year validity, records permittees keep and certificates from other provinces.
- Minors and the legal ageSaskatchewan's legal age of 19, selling or giving alcohol to minors, minors as patrons and employees in restaurants, lounges and taverns, family dining, retail stores and the parent exception.
- Checking IDThe legal duty to demand proof of age, SLGA's Check 25 standard, acceptable photo and secondary ID, examining ID and Saskatchewan licence security features, signs of a minor and ID checks on delivery.
- Intoxicated patronsThe ban on selling or supplying alcohol to anyone who appears intoxicated, common signs, when an intoxicated patron may wait inside, reducing the risk of intoxication, monitoring and staff drinking.
- Refusing entry and removing patronsThe right to refuse entry or ask someone to leave, re-entry the same day, disorderly conduct, practical steps with unruly patrons, limits on force, overcrowding and illegal activities on the premises.
- Hours of sale and serviceMaximum service hours of 9:30 a.m. to 2:00 a.m., New Year's Eve, the half-hour tolerance period, the 3:00 a.m. limit, retail store hours, Sunday brunch and family dining hours and delivery timing.
- Prices, promotions and advertisingSLGA minimum drink prices, two-for-one and happy hour rules, banned all-you-can-drink and games-of-chance pricing, treating, sample sizes, alcohol as prizes, cover charges, pay tied to sales and advertising near schools.
- Serving and handling alcoholLegal sources of alcohol, illegal and homemade alcohol, marrying bottles, measuring spirits, bottle pre-sales, self-serve dispensers, resealing wine and high-alcohol beer, bring your own wine, take-out and home delivery.
- Liability, inspections and penaltiesCommercial host liability in Canadian court cases, SLGA inspections, warnings, administrative penalties up to $10,000, suspensions and cancellations, review by the Licensing Commission and court fines.
- Impaired driving and alcohol in publicSaskatchewan's zero tolerance for new drivers, roadside suspensions for experienced drivers over .04, alcohol in vehicles, public places, the Report Impaired Drivers program and getting patrons home safely.