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Following Distance: the 2-Second Rule

A safe distance behind a vehicle is one of the most important rules for preventing accidents. Section 19 of Act 361/2000 Coll. states that a driver must maintain a distance behind the vehicle in front of them that allows for safe stopping.

In practice, the TWO-SECOND RULE is used to calculate safe distance.

Explanation

THE TWO-SECOND RULE:

How to use it: 1. Choose a fixed point on the road (a sign, a tree, a pole) 2. When the car in front of you passes that point, start counting: 'twenty-one, twenty-two' 3. If you reach that point BEFORE 'twenty-two', you are TOO CLOSE

Why two seconds?

• The average human reaction time is 1 second
• The remaining 1 second is for braking
• At a speed of 90 km/h = 2 seconds ≈ 50 meters
• At a speed of 130 km/h = 2 seconds ≈ 72 meters

WHEN TO INCREASE THE FOLLOWING DISTANCE to 3 seconds or more:

• In rain, snow, or ice
• In reduced visibility (fog, twilight)
• Behind a vehicle that may surprise you (beginner, cyclist)
• In a traffic jam on the highway

STOPPING DISTANCE = REACTION DISTANCE + BRAKING DISTANCE

1. REACTION DISTANCE: the distance you travel before you hit the brakes

• At 50 km/h: about 14 m (in 1 second)
• At 90 km/h: about 25 m
• At 130 km/h: about 36 m

2. BRAKING DISTANCE: the distance from the start of braking to a complete stop

• At 50 km/h: about 12 m (on dry road)
• At 90 km/h: about 40 m
• At 130 km/h: about 85 m

3. TOTAL STOPPING DISTANCE:

• At 50 km/h: about 26 m
• At 90 km/h: about 65 m
• At 130 km/h: about 121 m

ON WET ROADS, the braking distance increases by 50-100%! At 90 km/h on wet roads: about 80-100 m to stop.

Example

Example - why distance matters:

You are driving on the highway at 130 km/h behind a truck. The truck suddenly brakes hard.

• Your reaction time: 1 second = you travel 36 meters before you hit the brakes
• Braking distance: about 85 meters
• Total needed: 121 meters to stop

If you were only 30 meters behind the truck, you would collide at a speed of about 100 km/h!

If you follow the 2-second rule (72 m), you have a chance to stop safely.

In rain, you should be 3 seconds behind the truck (about 108 m).

Common mistakes

Common mistakes:

1. "Two seconds is always enough" - NO! In rain, fog, or on slippery roads, you need 3-4 seconds.

2. "At low speeds, I don't need to maintain distance" - YES, you do! Even at 30 km/h, you need space for reaction.

3. "Braking distance is the same on dry and wet roads" - NO! It is 2× longer on wet roads.

4. "Modern cars with ABS stop immediately" - ABS helps maintain direction, but it DOES NOT SIGNIFICANTLY SHORTEN braking distance on wet roads.

How to remember it

Practical summary:

The 2-second rule – how to follow it:

How to measure: Choose a fixed point by the road (a pole, a sign). When the car in front of you passes this point, start counting “twenty-one, twenty-two.” If you pass it sooner, you are too close.

When to increase following distance:

• Rain, wet → 3 seconds
• Snow, ice → 4–6 seconds
• Fog, poor visibility → 4+ seconds
• Night → 3 seconds
• Driving behind a truck (obscured view) → 3+ seconds

Reaction time: The average driver reacts in 1 second. In that time, at 50 km/h, you travel 14 m, at 90 km/h it is 25 m, at 130 km/h a full 36 m – and you haven't even started braking yet.

What the law says

Verbatim text of Act No. 361/2000 Coll., on road traffic, as in force on 1 January 2026. Quoted in Czech — the Czech wording is the binding one.

Check what you remember

Five questions from the official bank. The answer appears only after you choose — try to recall it first, that is what makes learning stick.

1. Question 1 of 5

   A round trip is considered to be:

   International occasional transport of persons on request along a pre-designated circular route, with the same group of passengers being transported by the same vehicle.A trip with a travel agency with a sightseeing purpose.Transport of persons on a public transport route through towns and villages where the starting and ending point of the journey is the same.

2. Question 2 of 5

   Combined transport is considered to be a transport system in which:

   Goods are transported in one and the same transport unit, also using rail and water transport.Persons use various types of transport, e.g. bus or train.It concerns transport services within domestic road transport.

3. Question 3 of 5

   In your view from the motor vehicle, you see children playing on the pavement. How will you behave?

   You will be prepared to brake with regard to the possibility of children running into the carriageway and will reduce your speed according to the circumstances.Because the children are on the pavement, you have no reason to increase caution or change your driving style.From a sufficient distance, you will alert the playing children to possible danger with an audible warning signal.

4. Question 4 of 5

   On roadside vegetation, unless permitted by local road regulations:

   The driver may stop for the time strictly necessary.The driver must not stop or park.The driver may stop but not park.

5. Question 5 of 5

   On a one-way road, the driver may stop and park:

   Only on the right.Only on the left.On the right or on the left.