Talk:Road signs in Thailand

Vienna Convention Type B
Some of the diagrams used in the article are actually of signs used in other countries -- especially Japan -- and while correct enough in overall design are, of course, frequently different in detail. One serious discrepancy is that mandatory directional signs in Thailand are of Vienna Convention Type B (and not Type A as in Japan): I've changed the Keep Left sign shown here accordingly. -- Picapica (talk) 12:19, 19 April 2013 (UTC)

Compulsory left turn
I regularly see the confusing sign "compulsory left turn" with white background, red rim and a curved left arrow, but no diagonal red bar. See a (non-free) picture here. &minus;Woodstone (talk) 18:25, 25 January 2017 (UTC)
 * That's a non-standard sign. Correct compulsory left turn signs have a white arrow on a blue background, although it seems even some police departments aren't aware of this. --Paul_012 (talk) 11:24, 26 January 2017 (UTC)
 * I know that's the international standard, but I don't remember ever having seen the blue one in Thailand. They always use the white/red one (without diagonal). &minus;Woodstone (talk) 18:26, 26 January 2017 (UTC)
 * They are used. See for example the signage at Phloen Chit Intersection. --Paul_012 (talk) 21:08, 26 January 2017 (UTC)
 * Indeed and thanks. Funnily enough a hundred meters further, at the entrance to the highway, they show the more usual model.
 * It leaves the question of whether we should include the red/white model in the list of signs on the page. It is quite common. &minus;Woodstone (talk) 07:58, 27 January 2017 (UTC)
 * From what I observe, it seems like the more permanent signs tend to follow the standard, while ad-hoc ones often don't. At any rate, we need a reliable source discussing the fact. The law clearly states that the white on blue is the correct one. (Though I note that the article currently includes a jumble of signs seemingly both specified by the law and not. Much clean-up appears needed.) --Paul_012 (talk) 13:59, 27 January 2017 (UTC)
 * In my view the article should not be based only on the law, but also include common practise in the country. We should describe reality, not the formal state. &minus;Woodstone (talk) 08:03, 28 January 2017 (UTC)
 * Of course. I have nothing against that; just pointing out that it'd be more difficult to find reliable sources that document such practices. --Paul_012 (talk) 05:03, 29 January 2017 (UTC)

This seems a valid reference:. &minus;Woodstone (talk) 17:12, 29 January 2017 (UTC)


 * Late reply (5 years later): The red-rim round sign was indeed previously correct. The oldest official document I found was a Proclamation of the Traffic Officer dated 31 March 1958. The blue sign was officially made the standard in 2004. --Paul_012 (talk) 07:29, 2 September 2022 (UTC)

A Commons file used on this page has been nominated for deletion
The following Wikimedia Commons file used on this page has been nominated for deletion: Participate in the deletion discussion at the. —Community Tech bot (talk) 12:04, 26 December 2018 (UTC)
 * Reflexivo Delineador THA 3.png

A Commons file used on this page has been nominated for deletion
The following Wikimedia Commons file used on this page has been nominated for deletion: Participate in the deletion discussion at the. —Community Tech bot (talk) 02:51, 23 April 2019 (UTC)
 * Thai road sign B-56.png

A Commons file used on this page or its Wikidata item has been nominated for deletion
The following Wikimedia Commons file used on this page or its Wikidata item has been nominated for deletion: Participate in the deletion discussion at the. —Community Tech bot (talk) 09:37, 15 May 2020 (UTC)
 * Thai Road sign I 56.png

Right-of-way at uncontrolled junctions?
Which right-of-way rule applies at an uncontrolled junction in Thailand? Some people claim that it is priority to the left (which obliges a vehicle driver to give way for every vehicle oncoming from the left - just as a driver must do for vehicles oncoming from the right in most European countries where priority to the right applies). 90.231.234.93 (talk) 12:05, 1 September 2022 (UTC)


 * That is correct, according to Section 71(1) of the Road Traffic Act, B.E. 2522. Not sure if most motorists actually know this, though. --Paul_012 (talk) 07:07, 2 September 2022 (UTC)
 * It seems that vehicle drivers often miss their duty to yield priority for a vehicle oncoming from a road on the left-hand side, mainly at three-way junctions and intersections between a big road and a smaller road. Drivers seem to have tendency to perceive that the bigger road, or the road going straight ahead at a t-junction, is a "priority road".
 * I personally think it is very unrealistic to have priority to the left/priority to the right at a three-way junction, obliging a vehicle driver to yield for a vehicle oncoming from a sideroad to the left/right.
 * In some countries, mainly UK and Australia, it's always the T-junction rule applying at a three-way junction, obliging a vehicle driver turning in a t-junction to yield for every vehicle approaching the junction (on the way straight ahead) and, if the driver turns right (in left-hand traffic), for vehicles turning left or (if two drivers both turn right) for the vehicle approaching from the left (and the road going straight ahead at a t-junction is normally also marked as "priority road"). Why doesn't the T-junction rule apply in for example mainland-Europe if it applies in Britain? 90.231.234.93 (talk) 20:31, 2 September 2022 (UTC)
 * According to Thai law, the priority-to-the-left rule only applies when neither intersecting road is designated as having right-of-way. at T-junctions and intersections between bigger and smaller roads, the ways you describe are usually designated (most often by road markings) as such. --Paul_012 (talk) 08:41, 5 September 2022 (UTC)