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When to Say When: 5 Signs It’s Time to Take a Loved One’s Car Keys

They’ve been drinking. Should you let them drive?

We all know the risks associated with driving under the influence. None of us wants our loved ones to take those risks. But, how do we know when they have reached their limit? When is it no longer safe for them to drive? When should we step in and stop them from getting behind the wheel?

To determine the answer, look for the following:

#1 They are Showing Visible Signs of Intoxication

This sign is usually easiest to spot. Slurred speech, loss of motor control, loss of inhibitions, and personality change are all red flags. If they exhibit these behaviors, they are not fit for the wheel.

#2 They Can’t Pass Police Field Tests

A quick and simple test you can perform on your loved one is to check for horizontal gaze nystagmus (HGN).

Ask them to follow your finger as you move it across their field of vision, without moving their head or neck. Move your finger from in front of their nose to the edge of their peripheral vision. If the eye movement is jerky rather than smooth, and/or “bouncy” when looking to the far right or left, take away the keys.

Additional tests include:

  • Walk a straight line, heel to toe.
  • Tip the head back, close the eyes, and touch the tip of the nose with the index finger.
  • Stand on one foot.
  • Recite the alphabet backwards.

#3 They’ve Had More Than One Drink Per Hour

Typically, it takes the liver one hour to process one ounce of liquor (one standard drink.) When higher amounts are consumed, alcohol accumulates in the blood and body tissues, resulting in high blood alcohol content (BAC).
One drink is considered:

  • 1 – 12 fl oz of beer
  • 1 – 5 fl oz of wine
  • 1 – 1.5 fl oz of hard liquor

If your loved one’s drinking rate is higher than one drink per hour, their body will not have had time to metabolize the alcohol, and they are not fit to drive.

#4 Their Blood Alcohol Level is Above the Legal Limit

This one seems obvious, but how can you know if this is the case? With today’s technology, it’s actually simple. If you know you will be encountering these situations, it may be worth investing in a portable breathalyzer.

Available as small as keychain-size, with disposable mouthpieces, it is easy to have one on hand. Affordable options can be found on Amazon.

While they may be resistant to using the device, the tangible evidence of an over-the-limit BAC (above .08) can help convince your loved one they shouldn’t drive. Even if it doesn’t, it can stiffen your resolve and assure you that you are doing the right thing by taking away the keys.

#5 You are Having Doubts

When it doubt, play it safe. If you doubt that they are safe to drive, don’t let them. They may get angry at the time, but “better safe than sorry” definitely applies here. It’s better to risk their anger than risk their life.

Consider Zero Tolerance

Because many factors influence the effects of alcohol on the body (weight, metabolism, food, medications) it is often difficult to apply hard and fast rules to this situation. One person may show visible signs of intoxication, while another may be just as unsafe to drive, but fool you with a stable appearance. For these reasons, the best option is simply no drinking and driving, period.

Additional Reading: Should Beauty Salons be Allowed to Serve Alcohol?

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