How do you know that no «official person» is responsible for the content in this page?

[จังหวัดของประเทศไทย] (https://th.wikipedia.org/wiki/จังหวัดของประเทศไทย)

Can you read Thai?

You can do an internet search by your own with:

จังหวัดของประเทศไทย ตัวย่อ อักษรโรมัน (Provinces of Thailand Abbreviation Roman)

Let me know if you could find a trusty source for the three-letter Latin province code!

Thank you

Yes not always – but sometimes Wikipedia is the best source you can get and until no Thai Official corrects the codes in their Thai Wikipedia Entry I will stick with it.

Yes, there is an «official» List with a three-letter Latin code for every Thai province, which can be found in Wikipedia:

[https://th.wikipedia.org/wiki/จังหวัดของประเทศไทย] (https://th.wikipedia.org/wiki/จังหวัดของประเทศไทย) (Thai)

Okay – thank you for your helpful comment and suggestion.

So you suggest to delete all the name:en values of roads in Thailand then? Normally OSM contributors in Thailand (mis)use the name:en to tag the Romanized version of a Thai name. And what about places? The often have name:en values too!

Should we delete all name:en values in Thailand then because it is a «misuse», a «disrespect» of the system and let only map renderer Romanize Thai names?

Theoretically you are right *name:en” is not the appropriate tag for Romanized Thai names – but it is the De Facto Standard here in Thailand.

I think ref values shouldn’t Romanized by automatic renderers.

The ref tag is a crucial one. These values should be defined – officially defined like in [WikiProject Thailand] (http://wiki.openstreetmap.org/wiki/WikiProject_Thailand) described.

There is a defined List of a three-letter Latin code of all 77 Thai provinces [here] (https://en.wikipedia.org/wiki/Provinces_of_Thailand) which could be used for a «International» reference instead of a Romanization of the two-letter Thai code.

But how to? How not to break rules? Can we define new rules for tagging Rural Road without breaking «fundamental» OSM rules?

Maybe here is a solution: [Key:ref] (http://wiki.openstreetmap.org/wiki/Key:ref) or more specific here: [Key:int_ref] (http://wiki.openstreetmap.org/wiki/Key:int_ref)

Example: highway=tertiary, ref=ชบ.1095

ชบ is the official Thai two-letter code of the province ชลบุรี (Chonburi) Romanization of ชบ renders ChB (ช=ch, บ=b) (ISO 11940, RTGS, ALA-LC)

Therefore an international reference of ชบ.1095 could be ChB.1095. Problem solved? – Not at all!

จบ is the official Thai two-letter code of the province จันทบุรี (Chanthaburi) Romanization of จบ renders CB (จ=c, บ=b) (ISO 11940) or ChB (จ=ch, บ=b) (RTGS) or ČhB (จ=čh, บ=b) (ALA-LC).

In the first case all three Romanization got the same result, but not in the second case. Even worse one method renders the same value for Chonburi and Chanthaburi and an other one uses a tonal mark in its representation.

This a clearly «no go» for Romanization.

Instead we should better use the already defined three-letter Latin provincial code like:

ชบ.1095 → CBI.1095 as an international reference

But how to use it? How to implement it smoothly into OSM? How not to offend the OSM hardliners?

There are several options:

1. highway=tertiary, ref=ชบ.1095
2. highway=tertiary, ref=ชบ.1095, nat_ref=ชบ.1095, int_ref=CBI.1095
3. highway=tertiary, ref=ชบ.1095; CBI.1095
4. highway=tertiary, ref=ชบ.1095; CBI.1095, nat_ref=ชบ.1095, int_ref=CBI.1095
5. highway=tertiary, ref=ชบ.1095, name=CBI.1095
6. highway=tertiary, ref=ชบ.1095, name:en=CBI.1095

Suggestions?