Legal working age for cashiers and bar girls

Legal age is now 20 years of age. Signs in Big C  etc


You might get told by a bar worker it's 21 to work there that's because they were told you must be over 20 and their minds don't work like yours LOL

Hello mate, thanks for your answer, but I am not asking that thing.  What I need to know is: when the law changed? Because in the past, it was allowed at 18 , I am pretty sure about that, but the law changed time ago (5 years, 10, 15 ?) I don´t know when it changed form 18 to 20. I heard it was in 23 of July from 2015, but I could not to confirm this information.
Regards.

Try Youth Protection Law
กฎหมายคุ้มครองเยาวชน

Was definitely before 2015 although maybe that is the Royal Decree date?

Thanks a lot for your answer, I am not sure, I am trying to figure out for a long time, but the information I got at the moment, it is not very clear and quite confuse. I will try to follow your clue about the law, many thanks. I found this Alcohol Beverage Control Act B.E. 2551 Sec 29 , but it does not say anything about working , just drinking, and this is what confuse to me a lot.

Regards.