Phayao Hospital declared a four-storey building that caught fire on Tuesday night off-limits Wednesday.
No one was hurt during the blaze, which broke out in this northern province at 7.45pm and spread along the fourth floor before it was brought under control 30 minutes later, said Phayao governor Narongsak Osotthanakorn, who visited the hospital Wednesday.
The floor was only used to keep documents while the lower three floors were not affected, he said.
The first floor serves as an emergency ward and the second runs a kidney dialysis centre, he said, adding the third floor is a "computer hub".
The governor said the emergency ward had been moved to another building close by while patients from the dialysis centre would be treated at nearby facilities.
Phayao Hospital director Jiraporn Phataranuthaporn said officials from the Department of Public Works and Town and Country Planning were examining the structure of the building.
She said the blaze caused at least 1 million baht in damages. Work is under way to recover a computer server containing a patient database. The hospital's computer system is likely to return to full functionality today, the director said.
Forensic officers said the fire was caused by a short circuit, according to Dr Jiraporn.
Mr Narongsak was the former governor of Chiang Rai. He oversaw the operation to rescue 12 young footballers and their coach trapped in Tham Luang cave in Chiang Rai this month.
In a separate move, Mr Narongsak told provincial authorities that water resource management would be prioritised, in addition to organic farming and tourism, to better serve the economy.
