Supachai Iemsuwan, former Chiang Mai governor, has issued an order to every district in Chiang Mai, referring to the Thailand Air Navigation Act (No. 14) 2019 Section 33 (effective since 26 May 2019) which doesn’t allow the public to light fireworks, lanterns, balloons or any other similar objects into the sky which would cause danger to aviation or carrier operations in safety zones. Those who violate the law can be jailed for not over 5 years or fined not more than 200,000 baht, or face both imprisonment and fine.
District chiefs have been told that there is a ban on the releasing of flying lanterns or similar objects in the following areas: all of Muang and Hang Dong districts, Saraphee (Tambon Khua Mung, Don Kaew, Tha Wangtan, and Nong Phueng), Mae Rim (Tambon Dong Kaew, Rim Tai and Mae Sa), and Sansai (Tambon Nong Harn)
As such Tambon Mae Hia is in the banned area and selling of such object are not allowed.
Photo credit: https://www.m-culture.go.th/chiangmai/ewt_news.php?nid=920&filename=index
As for districts and areas outside safety aviation zones, the permit to release is in accordance with announcement for measurements in lighting and releasing flying lanterns (announced 7th October 2011). (credit of announcement source: Chiang Mai News)
Flying lanterns can be released on Loy Krathong day (full moon day of Thai twelfth lunar month) (11 November 2019) and 12 November 2019, and 31 December 2019 from 7pm to 1am of the following day while smoke lanterns can be released between 10am till noon only on 11 November 2019. Those who want to light and release these flying objects must obtain a permit from district chiefs 15 days in advance. The selling of flying lanterns including smoke lanterns can be done only in the areas allowed by district chiefs only.