Key points
An expert driver looks 20 to 30 seconds ahead.
Source: Handbook p. 8-2
“An expert driver tries to keep looking 20 to 30 seconds ahead.”
Maine Driver's License Manual, Handbook p. 8-2Check your mirror for traffic behind you every 6 to 8 seconds.
Source: Handbook p. 8-3
“Check your mirror often for traffic behind you - every 6 to 8 seconds.”
Maine Driver's License Manual, Handbook p. 8-3On a wet road slow down 5 to 10 mph; on packed snow slow to half speed; on ice slow to a crawl.
Source: Handbook p. 8-6
“Wet road: Slow down 5 to 10 mph. Packed snow: Slow down to half speed. Ice: Slow to a crawl.”
Maine Driver's License Manual, Handbook p. 8-6Bridges and overpasses freeze first and dry out last.
Source: Handbook p. 8-7
“Be aware that bridges and overpasses tend to freeze first and dry out last.”
Maine Driver's License Manual, Handbook p. 8-7Perception time is the time it takes you to recognize you must stop; for an alert driver it averages three quarters of a second to 1 second.
Source: Handbook p. 8-7
“the time it takes you to recognize you must stop. The average perception time for an alert driver is ¾ to 1 second.”
Maine Driver's License Manual, Handbook p. 8-7The average driver's reaction time, to move a foot from the gas to the brake and begin braking, is three quarters of a second to 1 second.
Source: Handbook p. 8-7
“the time it takes for you to react and move your foot from the gas to the brake pedal and begin braking. The average driver has a reaction time of ¾ to 1 second.”
Maine Driver's License Manual, Handbook p. 8-7At 50 mph on dry pavement with good brakes, braking alone takes about 158 feet.
Source: Handbook p. 8-7
“At 50 mph on dry pavement with good brakes, it can take about 158 feet.”
Maine Driver's License Manual, Handbook p. 8-7Adding perception and reaction time nearly doubles that braking distance.
Source: Handbook p. 8-7
“Adding perception time and reaction time nearly doubles this distance.”
Maine Driver's License Manual, Handbook p. 8-7Headlights let you see clearly only about 250 feet, so over about 50 mph on a dark road you are driving blind.
Source: Handbook p. 8-8
“Headlights will let you see clearly only about 250 feet ahead. Therefore, if you drive faster than about 50 mph on a dark road, you are really "driving blind."”
Maine Driver's License Manual, Handbook p. 8-8Do not drive through large bodies of standing water; find another route.
Source: Handbook p. 8-7
“Do not drive through large bodies of standing water. If the roadway is flooded, find another route.”
Maine Driver's License Manual, Handbook p. 8-7
Numbers to know
| Number | What it means | Manual |
|---|---|---|
| 20 to 30 seconds | how far ahead an expert driver looks | Handbook p. 8-2 |
| 6 to 8 seconds | how often to check the mirror | Handbook p. 8-3 |
| 5 to 10 mph | how much to slow on a wet road | Handbook p. 8-6 |
| ¾ to 1 second | average perception time for an alert driver, and average reaction time | Handbook p. 8-7 |
| 158 feet at 50 mph | braking distance on dry pavement | Handbook p. 8-7 |
| 250 feet, 50 mph | how far headlights let you see, and the speed at which you outdrive them | Handbook p. 8-8 |
3 questions from the Maine practice test
1. What is the average perception time for an alert driver, according to the Maine manual?
- Three quarters to one second
- Two to three seconds
- Four to five seconds
- One tenth of a second
Show answer
Three quarters to one second. The manual places an alert driver's average perception time at three quarters to one second. Perception time is the interval needed to recognize that a stop is necessary, before physical braking begins. The longer ranges overstate the stated average, while one tenth of a second understates the time available in real driving. This interval is one part of total stopping distance, which also includes reaction and braking distance. Keep extra space when speed, visibility, or attention is less favorable than the ideal conditions used for the estimate.
2. What braking distance does the Maine handbook give at 50 mph on dry pavement with good brakes?
- About 500 feet
- About 30 feet
- About 158 feet
- About 1,000 feet
Show answer
About 158 feet. At 50 mph on dry pavement with good brakes, braking alone can take about 158 feet, and that comes after perception and reaction time. Headlights let you see clearly only about 250 feet ahead, so at night you must drive slowly enough to stop within that distance. Give yourself extra following distance before reducing speed or turning, and add more on wet or icy pavement.
3. How far ahead do headlights let you see clearly, according to the Maine handbook?
- About one mile
- About 1,000 feet
- About 50 feet
- Only about 250 feet
Show answer
Only about 250 feet. Headlights will let you see clearly only about 250 feet ahead, so never drive so fast that you cannot stop within the distance you can see with your lights; the handbook says that above about 50 mph on a dark road you are really driving blind. Maine law requires headlights anytime from sunset to sunrise, whenever visibility is too dim to see 1,000 feet ahead, and whenever the wipers are in constant use. High beams let you see twice as far as low beams, so use them when there are no oncoming vehicles.
Practice this topic
Lock it in with safe driving questions from the free Maine practice test. Every answer comes with a plain English explanation.
Source: the Maine Driver's License Manual, Section 8: Managing Time and Space. This lesson is a plain English summary, not the law itself; where it differs, the manual and the statute govern. Last checked 2026-09-27.