prohibition sign
Speed limit (40 km/h)
Thai road sign บ.32-40 — Speed limit (40 km/h). Meaning: Drivers must not exceed 40 km/h from this sign onward. Catalog status: additional official road-sign reference.
Thai name: ป้ายจำกัดความเร็ว
Independent English reference · Source: Department of Highways · Sign บ.32-40
Road response
On the road
Driver action
What should you do?
Reduce speed to 40 km/h or less from the point where this limit begins.
Exam-style scenario
Read the situation
The posted limit changes to 40 km/h as you leave a faster road and approach roadside activity.
Best response: Complete the speed reduction as the new section begins and remain at or below 40 km/h.
Sign comparison
Don’t confuse it
This sign
Speed limit (40 km/h)
Compare with
Speed limit (45 km/h)
Key difference
Read the complete numeral: this sign ends in 0 and caps speed at 40 km/h, while the similar sign reads 45.
Put sign knowledge into practice.
Answer exam-style questions about road signs, traffic lights, and lane markings in clear English.
