Tirayut Wongsantisuk and his wife moved to Chiang Mai in the 2010s, drawn by the hilly region's cool air and lush greenery.
But worsening air quality in the Thai city, especially during this time of the year, have prompted them to consider relocating for the sake of their children.
Two of their daughters have experienced frequent nosebleeds. "I've been thinking, maybe we really should move during this time... because if something bad happens to our child, we'll feel terrible forever," Tirayut , 41, told the BBC.
Smoke from raging fires have choked parts of northern Thailand this past week, with Chiang Mai ranking among the world's most polluted cities, according to monitoring group IQAir.
A thick blanket of haze hovered over the horizon when BBC Thai visited Tirayut and other families in Chiang Mai, covering what once were mountainous views. There was a persistent burning smell in the air.
