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Driver Factors

Your vehicle may be ready to go, but your safety depends just as much on the following driver factors.


Inattention great enough to cause a crash can result from driving distractions or lack of sleep.

Did You Know?

Driver distraction and inattention to road and traffic conditions are responsible for 25 to 30 percent of police-reported traffic crashes. This adds up to approximately 1.2 million crashes every year.

Driving Distractions

Anything that causes you to 1) take your attention away from driving, 2) take your eyes off of the road, or 3) take your hands off of the wheel is a distraction. You will not be able to react as quickly if you are:

  • Eating, drinking and smoking. These all create safety problems because they often require you to take your hands off of the wheel and take your eyes off of the road. Drivers who eat or drink while driving have trouble controlling their vehicle, staying in their lane and have to brake more often.
  • Adjusting audio devices such as: radio, cassette, CD, iPod/Mp3 player. NOTE: headphones/ear pieces can only be used in one ear for communication purposes.
  • Talking on a cellphone (whether it is hands-free or not). Please refer to Chapter 5 for more information about anti-texting laws.
  • Interacting with other passengers. This can be just as much of a problem, particularly for teenage drivers. If you are a teen driver with other teens as passengers, statistics show you are more likely to have a crash than if you are driving alone or are driving with adult passengers.
  • Searching for or moving an object in the vehicle.
  • Reading, writing, or texting.
  • Personal grooming (combing hair, applying makeup).
  • Rubbernecking when passing a crash scene or a work zone.
  • Looking at people, objects, or events happening off of the roadway.

Did You Know?

Research has found a normal, undistracted driver fails to notice an important road event such as another driver making a mistake, 3 percent of the time. An adult dialing a cellphone misses the same event 13 percent of the time. A teenager dialing a cellphone misses it 53 percent of the time.

Lack of Sleep

When you are tired, you react slower, your judgment and your vision are impaired, and you have problems with understanding and remembering things. Driving while fatigued has similar effects as driving under the influence of alcohol. Being awake for 18 hours impairs your driving about as much as a blood alcohol level of .05 percent. Being awake for 24 hours in a row impairs your driving as much as having a blood alcohol level of .10 percent. If you are tired enough, you may fall asleep and never even know it. Sleeping behind the wheel for even a few seconds is enough to kill you. Teens who sleep less than eight hours a night are at increased risk of vehicle crashes. The best thing to do if you begin to feel tired while driving is to stop driving.

Did You Know?

  • Every year across the U.S., falling asleep while driving causes at least 100,000 crashes.
  • 1,500 people die and 40,000 are injured in these crashes.
  • Of the 100,000 vehicle crashes linked to drowsy driving each year, almost half involve drivers between 15 and 24 years of age.

Health Factors

Your driving safety can be affected by problems with vision, hearing, or medical conditions.

  • Have your vision checked every one or two years. Your peripheral (side) vision, your distance judgment, and your ability to see in low light conditions can deteriorate due to disease and as a normal part of the aging process. You will not always know this and be able to take corrective action unless your vision is examined regularly. If you need to wear glasses or contacts, make sure you use them every time you drive.
  • Hearing can warn you of dangers you do not see, like another vehicle in your blind spot. Hearing is also important to let you know an emergency vehicle (police, fire, ambulance) is approaching or to detect a train at a railroad crossing.
  • Various diseases and medical conditions, even little problems like a stiff neck or sore knee, can have a serious impact on your ability to control your vehicle effectively. The most dangerous health problems include seizure disorders that cause loss of consciousness, diabetes, and heart conditions. In Pennsylvania, physicians must report to PennDOT individuals whom they have diagnosed as having a condition that could impair their ability to drive safely.

Alcohol And Driving

  • In Pennsylvania and across the nation, drinking drivers are responsible for thousands of traffic deaths and injuries. Approximately 40 percent of all traffic deaths involve drinking drivers.
  • Recent Pennsylvania statistics show that 30 percent of drivers ages 16 to 20 who died in motor vehicle crashes had been drinking. This is despite the fact that here in Pennsylvania, as well as in every other state in the U.S., there are zero tolerance laws, meaning you may not drink if you are under age 21.
  • If you are a driver under age 21 and your blood alcohol concentration (BAC) is .02 percent or more, you are considered to be driving under the influence (DUI).
  • Even the smallest amount of alcohol will reduce your concentration, perception, judgment, and memory, and your driving skills will suffer. No one can drink and drive safely.
  • As alcohol builds up in your blood, your driving errors will increase. Your vision and judgment will be affected, your reactions will slow down, and you will lose your ability to control your vehicle safely and effectively. And, at the same time, alcohol robs your skills, making you feel dangerously confident. So, drinking drivers can be out of control and not even know it.
  • Many people believe only heavy drinking is risky. This is not true. Even drivers whose blood alcohol level is .04 (half of the "legal limit" of .08 for an adult 21 years of age or older) are between two and seven times more likely to be involved in a crash than drivers who have no alcohol in their blood. Even if your blood alcohol level is well below the legal limit, you will still endanger your life and the lives of others. The only safe amount of alcohol you can drink, and then drive, is zero.

Did You Know?

A female who weighs 110 pounds will have a BAC of .03 after drinking just 8 oz. of light beer – that’s less than one full bottle or can. A 140- pound male will have a BAC of .025 after a full 12 oz. bottle or can of light beer.

  • Alcohol affects individuals differently. Your blood alcohol level is affected by your age, weight, gender, physical condition, amount of food consumed, and any drugs or medication you have in your system. In addition, different drinks may contain different amounts of alcohol too. Make sure you know how much alcohol is in the drinks you consume. You should consider one drink to be 1.5 oz. of 80 proof liquor, 12 oz. of regular beer, or 5 oz. of wine.
  • To manage your drinking responsibly, do not drink more than one drink per hour, if you are of legal drinking age. It takes a person of average weight at least one hour to process the alcohol in every drink. More than one drink per hour is very likely to push your blood alcohol level over the legal limit.
  • The one drink per hour rule does not work for everybody, though. Alcohol is more concentrated in smaller people, and because of the differences in the way our bodies process alcohol, a woman drinking an equal amount in the same period of time as a man of the same weight may have a higher blood alcohol level.
  • Only time will "sober you up." You cannot reduce your blood alcohol concentration level by drinking coffee or other caffeinated beverages, or by taking a cold shower.

Did You Know?

In the U.S., one person dies every half hour and one person is injured every two minutes, because someone was drinking and driving.


Refer to Chapter 4 for more information about the penalties for underage drinking and driving under the influence.

Drugs and Driving

Driving impaired is both illegal and deadly. Not only does alcohol impair your ability to drive safely, many illegal, prescription, and over-the-counter drugs can also impair your ability to drive safely. Drugs other than alcohol are involved in approximately 20 percent of deaths among motorists each year. Additionally, combining drugs and alcohol further increases the side effects and greatly increases the risk of causing a crash.

Drugs affect your brain function and can seriously impair your ability to drive safely. For example, marijuana can slow reaction time, impair the judgment of time and distance, and decrease coordination. Cocaine or methamphetamine can cause a driver to be aggressive and reckless when driving and certain kinds of sedatives can cause dizziness and drowsiness. Opioids can make you drowsy and can slow reaction time. Prescription and over-the-counter drugs such as sleeping pills, cough medicines, antihistamines, and decongestants can affect your driving skills in a variety of ways. It is always important to review warning labels about the medication's side effects prior to driving. If you have any questions about a medication's side effects, it is important to consult with your doctor or pharmacist before driving. Remember: When the warning label states "Don't operate heavy machinery," your vehicle is considered heavy machinery!

If you are concerned about a loved one's or your own substance use, the PA Get Help Now helpline is available at 1-800-662-HELP (4357). This toll-free resource is staffed 24/7 to answer your questions and connect you to treatment providers.

Did You Know?

• According to the NHTSA 2013-2014 Roadside Survey of Alcohol and Drug Use by Drivers, nearly 1 in 4 drivers tested positive for at least one drug that could affect safe driving skills.

• 43% of drivers killed in crashes tested positive for drugs… 37% tested positive for alcohol.

• Prescription drugs can also affect driving. Talk to your doctor when starting any new medication and make sure you are aware of any potential side effects.

 Content Editor ‭[2]‬