Driver license the official handbook

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©2017 Florida Department of Highway Safety and Motor Vehicles
Construction/Maintenance Signs & Signals
Various traffic control devices are used in road 
construction and maintenance work areas to direct 
drivers and pedestrians safely through the work site. Be 
prepared to reduce your speed and use caution when 
directed to do so by a sign, flagger, or law enforcement 
officer. Failure to do so is illegal and is dangerous to 
those working in the construction zone. (Signs will 
indicate where speeding fines will be doubled when 
workers are present).
Construction and Maintenance Signs.
 The signs—
usually diamond shaped and/or orange in color—notify 
drivers of unusual or potentially dangerous conditions 
near work areas. 
Channeling Devices
  • Barricades, vertical panels, drums, and cones. 
  • Alert drivers of unusual or potentially dangerous 
conditions in highway and street work zones.
  • Guide drivers safely through the work area.
  • May be equipped with warning lights at night.
  • Stripes on barricades and panel devices slope 
downward in the direction traffic must travel.
Flashing Arrow Panels.
 Used both during the day 
and at night to give advance warning and directional 
information when it is necessary to move to another 
lane.
Flaggers.
 Are people who work in roadway 
construction/maintenance zones to stop, slow, or guide 
traffic safely through the area. Flaggers wear bright 
colored/fluorescent vests or jackets and use red flags or 
signs to direct traffic through work zones.

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The Official Florida Driver License Handbook—rev. 051417
  
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DRIVING SAFELY
Speed Limits
Obeying speed limits improves safety by reducing the probability and 
severity of crashes. Speed limit signs tell you the maximum safe speed when 
both weather conditions and visibility are favorable. 
Speeding is extremely dangerous. The faster you drive, the greater the 
impact or striking power of your vehicle:
  • When you double the speed of a car, you increase its force of impact 
four times.
  • When you triple the speed of a car, you increase its force of impact  
nine times.
Speeding is against the law. You must obey the speed limit and you are 
responsible for knowing the speed limit when you are driving. (The 
“speeding buffer” is a myth; you are not “allowed” to drive up to 10 mph 
over the speed limit.) Observe and obey posted speed limit signs. Speeding is 
the #1 citation written for teens. (Source: DHSMV.)
Florida Standard Speed Limits
School Zones
20 mph
Municipal, Business, or Residential Area
30 mph*
Streets and Highways
55 mph*
Rural Interstate
70 mph**
Limited Access Highways 
(see definition pg. 34)
70 mph
*maximum speed except where otherwise posted.
**on some rural Interstate highways.
Speed limits show the fastest speed you may drive under ideal conditions. 
You are responsible for adjusting your driving speed to the weather, 
roadway, and traffic conditions. For example, during a storm, you should 
drive slower than the posted speed. The safest speed is the one that allows 
you to have complete control of your vehicle and avoid collisions.
However, driving too slowly is also against Florida law. You must not drive 
so slowly that you block or delay traffic moving at normal, safe speeds. You 
should drive with the flow of traffic, within the speed limit. When driving 
slower than the flow of traffic, keep right so others may safely pass. On 
highways, when the posted speed limit is 70 mph, the minimum speed 
limit is 50 mph.

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©2017 Florida Department of Highway Safety and Motor Vehicles
Braking Distance
Perception Distance: 
how far your vehicle travels—in ideal conditions—
from the time your eyes see a hazard until your brain recognizes it. 
Perception distance can be affected by mental and physical conditions, 
medication, as well as visibility and the hazard itself. The average perception 
time for an alert driver is ¾ second to 1 second.
Reaction Distance:
 how far you will continue to travel after seeing the 
hazard until you physically hit the brakes. The average driver has a reaction 
time of ¾ second to 1 second. At 50 mph this accounts for 55 feet traveled.
Braking Distance:
 how far your vehicle will travel—in ideal conditions— 
while you are braking. At 50 mph on dry pavement with good brakes, it 
can take about 158 feet.
Total Stopping Distance:
 the total minimum distance your vehicle will 
travel—including perception distance, reaction distance, and braking 
distance—until you can bring your vehicle to a complete stop. At 50 mph, 
you will travel a minimum of 268 feet...nearly the length of a football field. 
High speeds greatly increase stopping distances and severity of crashes. The 
faster you drive, the greater the impact or striking power of your vehicle. 
  • Double your speed from 20 to 40 mph, the braking distance and 
impact are 4 times greater. 
  • Triple the speed from 20 to 60 mph, the braking distance and impact 
are 9 times greater. (Stopping distance is equal to a football field.) 
  • Quadruple your speed from 20 to 80 mph, the braking distance and 
impact are 16 times greater. 
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