Safe driving behaviour is one of the study areas behind the driver theory test in Ireland, where the car test asks 40 questions in 45 minutes and 35 correct answers pass. This lesson gives the rules, the law behind them and questions on this area. Source: Citizens Information, page edited 6 May 2026, checked on 15 September 2026.
By the Irish Mock Test teamFacts checked 15 September 2026How we check facts
A child under 3 must travel in an appropriate child restraint, and so must a child of 3 or over who is under 150 centimetres tall and under 36 kilogrammes.
Both conditions have to hold before a child is outside the rule, and a taxi may carry a child under 3 in a rear seat where no restraint is available.
This area covers what you do for the people in your vehicle and for the people around it: seat belts, child restraints, loads and overhangs, tyre condition, helmets and what happens when something goes wrong on the road. Almost all of it sits in Regulations with a figure attached, so a question here usually turns on a number or on which person carries the duty.
The rules
Every adult in a car, van or truck must wear a seat belt where one is fitted.
The duty sits on the person in the seat, and it applies in the back as much as in the front.
A child under 3 must travel in an appropriate child restraint, and so must a child of 3 or over who is under 150 centimetres tall and under 36 kilogrammes.
Both conditions have to hold before a child is outside the rule, and a taxi may carry a child under 3 in a rear seat where no restraint is available.
A load may overhang the side by no more than 300 millimetres and the rear by no more than 3 metres, and a rear overhang of more than 1 metre needs a red warning flag or marker by day.
Bikes on a rack, timber and ladders are the everyday cases, and the marker is what tells the driver behind you where your vehicle actually ends.
3 questions on the rules above before you read on.
1 of 3
Question 1
Which tyre condition is enough on its own to make the tyre illegal?
AA clean tread with the correct pressure
BA mark that does not reach the tyre ply
CA shallow surface scratch with no exposed cord and no damage beneath it
DA bulge, tear, exposed cord, or qualifying cut that reaches the plyCorrect answer
Show the answerHide the answer
Correct answer: D
Regulation 55(1)(a) to (e) and (h) of the Road Traffic (Construction and Use of Vehicles) Regulations 2003 makes any listed defect sufficient, including a bulge, tear, exposed ply or cord, or a cut reaching the ply that exceeds 25 mm or 10 per cent of section width.
Move the vehicle off the carriageway to the left, contact the Gardaí from the nearest telephone and stay no longer than you need to. Stopping and parking are otherwise banned there, and the hard shoulder is not a carriageway. Those duties are in article 33 of the Road Traffic (Traffic and Parking) Regulations 1997.
Why is this area called safe driving behaviour?
Because that is the wording the Road Safety Authority and the test operator use for it, while Citizens Information calls the same area good driving behaviour. The official sources disagree on the label, so both wordings are shown here rather than one being picked over the other.
On the road
Loading the car for a day at the beach
Two children are coming with you. The younger is 2, so an appropriate child restraint is required.
The older is 6, 115 centimetres and 21 kilogrammes, which is under both thresholds, so a restraint is required there too.
The only spare seat is in front, and a rearward-facing restraint may not go there while the airbag is active, so it stays in the back.
The bike on the rear rack sticks out about 1.2 metres, over a metre and well under three, so it needs a red flag or marker by day.
Last checks: tread depth in the main grooves all round, and every adult belted before you move off.
Where learners go wrong
Using an age threshold borrowed from another country. The Irish rule is a height and weight pair, and both parts have to hold.
Blaming the teenager in the back. The driver is responsible for every passenger under 17.
Stretching the airbag rule to forward-facing seats or to side airbags.
Answering 1 millimetre for a car tyre. That is the motorcycle figure, and a car needs 1.6 millimetres.
Treating hazard warning lights as permission to stop or park. No provision read gives them that effect.
A family boards a coach fitted with passenger seat belts. Who must use a belt or suitable child restraint?
AOnly passengers in the front row
BOnly passengers travelling on a motorway
CAdults only
DAdults and children aged 3 or overCorrect answer
Show the answerHide the answer
Correct answer: D
The 2006 Safety Belts Regulations, regulation 9, require adults and children aged 3 or over on a bus or coach with fitted belts to use the belt or child restraint.
A baby is travelling in a car for a brief local journey. Which restraint meets the general rule?
AAn appropriate child restraintCorrect answer
BAn adult's arms in the back seat
CA shared adult seat belt
DThe car's adult belt on its own
Show the answerHide the answer
Correct answer: A
Regulation 6 of the 2006 Safety Belts Regulations requires a child under 3 to be secured in an appropriate child restraint, regardless of journey length.
For the car seat belt rule, from what age is a passenger personally responsible for wearing a fitted belt?
AFrom age 14
BFrom age 16
CFrom age 17Correct answer
DFrom age 18
Show the answerHide the answer
Correct answer: C
The driver duty in the 2006 Safety Belts Regulations, regulation 5(2), (3), covers passengers under 17. From age 17, the passenger has the adult duty personally.
You are choosing a child seat. Which option meets the approval and fitting rule?
AA seat approved to UN ECE Regulation 44/03 or Regulation 129, fitted as the manufacturer instructsCorrect answer
BAny seat that fits firmly in the car
CAny child seat sold in an Irish shop
DAn approved seat fitted in any way that feels secure
Show the answerHide the answer
Correct answer: A
Regulation 3 of the 2006 Safety Belts Regulations, as substituted in 2014, requires approval to UN ECE Regulation 44/03 or Regulation 129 and fitting to the manufacturer's instructions.
A 9-year-old is 135 cm tall and weighs 30 kg. The car has rear belts and room for a child seat. What must be used?
AThe adult belt alone because the child is over 125 cm
BAn appropriate child restraintCorrect answer
CNo restraint because the child is over 25 kg
DThe adult belt alone because the child is over 8
Show the answerHide the answer
Correct answer: B
The child definition and restraint rule in the 2006 Safety Belts Regulations, regulation 2(1) and regulation 7, cover a person under 150 cm and under 36 kg.
A driver who was not wearing a seat belt pays the fixed charge. How many penalty points apply?
A2 penalty points
B3 penalty pointsCorrect answer
C5 penalty points
DA fine with no penalty points
Show the answerHide the answer
Correct answer: B
The current Road Traffic Act 2002, Schedule 1, Part 7, applies 3 penalty points when the fixed charge is paid. The 5-point value applies on conviction.
Source: Road Traffic Act 2002 (No. 12 of 2002), Schedule 1, Part 7, references 1 to 6, as substituted by Road Traffic Act 2014, section 10(f), checked on 2026-09-15.
Question 15
Where must a car tyre have the required 1.6 mm tread depth?
AAt one measured point anywhere on the tyre, regardless of the rest of the tread
BIn a continuous band all round, across the central three quarters of the treadCorrect answer
COnly on the outer edge of the tread
DAcross one quarter of the tread at the front
Show the answerHide the answer
Correct answer: B
Regulation 55(1)(f) of the Road Traffic (Construction and Use of Vehicles) Regulations 2003 requires the 1.6 mm depth continuously around the tyre across the central three quarters of its tread width.
A 4-year-old is under 150 cm and under 36 kg. The car has a suitable booster seat, rear belts and enough room. What should be used?
AAn adult belt alone because the child is over 3
BNo restraint on a local road
CAn adult's seat belt shared with the child
DThe appropriate child restraintCorrect answer
Show the answerHide the answer
Correct answer: D
Regulation 7, read with the child definition in regulation 2(1) of the 2006 Safety Belts Regulations, requires an appropriate restraint for this child aged 3 or over.
You want to place a rear-facing baby seat in front of an active frontal airbag. What does the rule require?
ADo not use that position unless the airbag is deactivatedCorrect answer
BPush the passenger seat fully back
CUse it only for a short journey
DUse it once the baby reaches a set weight
Show the answerHide the answer
Correct answer: A
The 2006 Safety Belts Regulations, regulation 8(2), prohibit a rear-facing restraint in front of an active frontal airbag unless that airbag is deactivated.