Tool Kit
Impaired Driving
Substance-related impaired driving is one of the leading contributors to crashes in BC. It’s also one of the most preventable. Learn how to spot the warning signs of alcohol and drug impairment, and create a policy that sets clear expectations and consequences for it.
How alcohol, drugs affect driving
Substance-related impairment reduces a driver’s mental and physical functions. It affects thinking and decision making, leading to greater risk-taking at the wheel. It also slows reaction time and reflexes, reduces attention span and ability to track moving objects, distorts perception of time and distance, and impairs coordination and lane control.
The most common substance-related causes of impairment in the workplace are the use of:
- Alcohol
- Cannabis
- Illegal drugs
- Prescription drugs
- Over-the-counter medications
Mixing cannabis with alcohol or other drugs makes impairment worse. Even if each substance is consumed in small amounts, together they greatly increase crash risk.
Even small amounts of alcohol can impair the ability to drive. A blood alcohol concentration (BAC) between 0.05% to 0.08% significantly increases crash risk and could lead to a suspension of driving privileges. At 0.08% BAC or higher, drivers are legally impaired in BC and can be arrested.
Alcohol affects everyone differently, but for most people, impairment begins with the first drink. Tolerance does not eliminate risk. Frequent drinkers may feel fine but their ability to drive safely is still reduced.
Alcohol stays in the bloodstream until the body fully metabolizes it. This can take several hours, meaning drivers may still be impaired the morning after drinking the night before.
Driving within 3 hours of using cannabis can double the risk of a crash.
The effects of cannabis vary widely from person to person. Impairment depends on:
- How it is used (smoked, vaped, or eaten)
- How much is ingested
- How recently it was used
- How often it is used
- The type of cannabis and how strong it is, even for medical cannabis
For most users, cannabis effects can last up to 5 hours after smoking and 6 to 12 hours or more after consuming edibles. Even after the “high” wears off, lingering effects can still impact coordination, reaction time, and judgment.
Tetrahydrocannabinol (THC) can linger in the body for weeks. As a result, drivers can test positive for it even when well below intoxication or impairment level.
The legal consequences of impairment
Substance-related impairment can lead to driving suspensions, vehicle impoundment, and invalidated insurance policies. Penalties vary depending on the level of impairment. Harsher consequences are likely for repeat offenses, higher blood alcohol content, or if illegal drugs are involved.
In BC, it is illegal to have cannabis in a vehicle unless it’s in a sealed package and not readily accessible to the driver or passengers.
In addition, workers who drive while impaired risk exposing themselves, their supervisor, and their employer to legal liability. Penalties may be levied under the Motor Vehicle Act, the Workers Compensation Act, civil law, and criminal law, especially if a crash injures someone.
Warning signs of impairment
Warning signs and symptoms of substance-related impairment may vary from person to person.
General signs of impairment include:
- Alcohol or drug odor, glassy or red eyes, unsteady gait, slurring, poor coordination
- Reduced productivity or work quality
- Unusual or erratic behaviours, reactions, or speech
- Making unusual/frequent mistakes
- Being late for work, taking longer or more frequent breaks
Impaired workers may not recognize their own condition. It’s important for employers, supervisors, and co-workers to stay alert and act when they see warning signs.
Fatigue is also a major cause of impairment. Review our Driver Fatigue Tool Kit to learn more about warning signs and how to prevent fatigue.
What employers can do to prevent impaired driving
Safety regulations require employers to identify any impaired employee and take appropriate steps to address the issue. Impaired employees can’t be assigned, or allowed, to drive. They also can’t remain at the workplace while their ability to work safely is affected by alcohol, drugs, or any other substance.
These responsibilities apply whether employees drive a company vehicle or their own vehicle for work. Learn more about employer legal responsibilities.
Employers can take several steps to address substance-related impairment:
A clear impairment policy is essential for every workplace. It should explain expectations for workers to be fit for duty, prohibit substance use before or during work, define impairment thresholds, specify testing protocols, and outline consequences for violations.
Our Impairment Policy template (Word) can be customized to any organization’s needs. Involve employees by asking them to review and help adapt it to your workplace. Have employees sign the final version to show they understand and agree to follow it. Give them a copy and put a copy in their personnel file.
When creating an impairment policy, keep in mind current occupational health and safety regulations, human rights and labour laws, and industry standards. Also keep in mind your organization’s capacity and commitment to uphold the policy.
Your policy should cover:
- Roles, responsibilities, and expectations
- Your confidential reporting process
- How reports are investigated
- Steps to accommodate affected workers, such as reassigning tasks or adjusting shifts
Get more information by reviewing WorkSafeBC’s Guide to Managing Workplace Impairment and Developing an Impairment Policy.
Commit to an annual policy review to ensure your guidelines remain current and effective.
Employers need to ensure that employees, supervisors, and managers receive education and training on workplace impairment. Training should cover:
- How impairment affects a person’s ability to work safely
- How to recognize warning signs
- Your organization’s impairment policy
- Steps to accommodate affected workers, such as reassigning tasks or adjusting shifts
- Available supports, such as employee and family assistance programs
Use WorkSafeBC’s Substance Use and Workplace Impairment Toolbox Meeting Guide for a staff discussion.
Supervisors should receive additional guidance to help them identify and manage impairment. Review your impairment policy with them and address their questions. Walk them through a real or hypothetical scenario so they clearly understand their role and responsibilities.
When safety becomes part of everyday workplace conversations, employees are more likely to make the right choice on and off the clock.
Encourage workers to look out for each other by making sure no one gets behind the wheel impaired. Plan ahead to have a designated driver after any workplace event involving alcohol. Provide information on safer ride options such as taxis, ride hailing or carpooling after long shifts or late nights.
Address common misconceptions, especially among younger workers. They may think that cannabis is safer than alcohol or that being “a little buzzed” won’t affect job performance. Reinforce the point that any level of impairment increases crash risk, and that driving for work while impaired endangers both the worker and the business.
Whenever workplace impairment is suspected or reported, employers and supervisors need to take immediate action. The procedure could include some of the following steps:
- Speak to the employee privately, with another person present as a witness.
- Remove any stigma regarding substance use. State concerns about safety for the employee and others.
- Ask them to explain what is going on.
- Discuss options according to your impairment policy.
- Document the conversation and actions taken.
Review the Canadian Centre for Occupational Health and Safety impairment resources for more information.
What drivers can do to prevent impairment
Staying fit to drive is part of every worker’s safety rights and responsibilities. Prevention also comes down to the choices you make before and during a shift. Here are key actions you can take to help ensure you’re always ready to drive safely:
- Know and follow your employer’s impairment policy
- Don’t drive if impairment may endanger you or anyone else
- Notify a supervisor if your ability to work safely is impaired for any reason
- Notify a supervisor if you see a co-worker who appears to be impaired
You can also do the following to help keep yourself and others safe:
Refrain from or limit your use of alcohol and drugs before upcoming shifts. If you do use alcohol or cannabis, give your body time to fully metabolize before your work shift begins. Remember that “morning after” impairment is common.
Review prescription and over-the-counter medications for side effects such as drowsiness, slowed reaction time, or dizziness. Ask your doctor or pharmacist if it’s safe to drive while taking them.
Combining alcohol, cannabis, or medications multiplies impairment risk even if each substance is taken in small amounts.
If you’re struggling with substance use, contact your employee assistance program, talk to a supervisor, or seek professional support.
For more tips, review our Driver Health and Wellness Tool Kit.