PETALING JAYA (The Star/Asia News Network) - After several days of good air, many areas in Malaysia endured smog-filled skies on Sunday (Oct 18) as the Air Pollutant Index (API) readings breached the unhealthy level.

More areas recorded unhealthy air at 1pm Sunday compared to earlier in the day.

Batu Muda recorded an Air Pollutant Index (API) of 103, with Seremban (102) and Nilai (104) in Negri Sembilan also moving into the unhealthy air range.

As of 1pm, Tawau in Sabah recorded the highest reading at 124, followed by Malacca City (114), Port Klang (110), Banting (109), and Bukit Rambai (106).

In Sarawak, the air quality in Samarahan registered an API of 109 and Kuching 102.

An API of between 0 to 50 is considered good, 51 to 100 (moderate), 101 to 200 (unhealthy), 201 to 300 (very unhealthy), 301 and above (hazardous).