A total of 158 flights at three airports have been cancelled or rescheduled for this week's three-day Loy Krathong festival, according to Airports of Thailand Plc (AoT) president Nitinai Sirismatthakarn.
Mr Nitinai said Chiang Mai, Chiang Rai and Hat Yai airports' flight schedules were trimmed from Tuesday until tomorrow for safety reasons, as lanterns are released into the sky to celebrate one of the year's most important holidays.
At Chiang Mai airport, 60 flights are being cancelled and 88 rescheduled. In Chiang Rai, four flights will be cancelled with four rescheduled.
Two flights are being cancelled at Hat Yai airport.
Loy Krathong falls on Thursday, but in the North the festivities last longer than a day. People often celebrate by setting a krathong -- a basket laden with coins, candles and their wishes for the future -- adrift on a canal or river together with friends or loved ones.
The AoT president is also calling on revellers to cooperate by not flying hot-air or smoke-filled lanterns and balloons.
He also asked people to refrain from lighting firecrackers or shooting beams of light into the sky with lasers during the festival as that can interfere with aircraft operations and signals, he said.
As for Chiang Mai and Chiang Rai, where releasing lanterns is part of the local celebrations, he said communities are being urged to comply with the AoT's recommendations.
All three airports have been instructed to keep the public informed of any updated safety precautions, and distribute brochures to ensure these are properly understood during the festival.
Meanwhile, the Bangkok Metropolitan Administration (BMA) has closed 88 piers along the Chao Phraya River as well as the city's canals to safeguard the public.
Governor Aswin Kwanmuang said the decision to close 45 river piers and 43 canal piers came in the wake of a recent inspection by officials who determined they were not fit for use on such occasions, which draw large crowds.
The governor led the inspection from Tha Chang Pier to the pier on Rama 8 Bridge. He said signs are being installed at the others to inform the public how many people each pier can accommodate. City officials, volunteers and police will be deployed there.
The BMA will begin a clean-up campaign shortly after midnight Thursday at public waterways and 30 public parks that are staying open for the festival, he added.