Thailand's domestic Don Mueang Airport, which was forced into closure for over four months, resumed normal service on Tuesday.

To rehabilitate the airport, which is located on the northern outskirt of Bangkok, the government earmarked 392 million bath ( 12.8 million U.S. dollars) and the Airports of Thailand Public Company Limited (AoT) pulled 1.2 billion bath (39 million dollars) of its own budget, according to AoT.

Assisted by experts from the Department of Health, Faculty of Public Health and Mahidol University, AoT applied sanitary measures kill microbes and odor caused by mud and moss clinging on the building and air condition system.

Prime Minister Yingluck Shinawatra declared the airport ready for commercial flights at a reopening ceremony Monday afternoon.

Patee Sarasin, chief executive of Nok Air, said the budget carrier would resume 82 normal daily flights at Don Mueang Airport, beginning at 6am on Tuesday. The airline moved temporarily to Suvarnabhumi Airport during the flood crisis.However, Orient Thai Airlines, another budget carrier based in the airport, has not yet decided on a time back.

Don Mueang Airport had served as the capital city's main airport since 1920s. It was closed in 2006 following the opening of the new Suvarnabhumi Airport and was opened again after a big renovation in March 2007 to run domestic flights.

Last October, the airport was abruptly shut down as flood water encroached into its buildings and runways. The government's flood relief operation center, which took shelter in the airport, was forced to move out.