Johor, occupying the top four spots, appeared to have fared the worst as of 6.30pm, with Larkin, Batu Pahat, Pasir Gudang and Kluang recording API readings of 161, 159, 158 and 156, respectively.

They were followed by Cheras, Kuala Lumpur (155), Nilai, Negeri Sembilan (153), Putrajaya (152), Segamat, Johor (152), IPD Serian (152), Tangkak, Johor (124), Bukit Rambai, Melaka (120), Johan Setia, Selangor (118), Kuching, Sarawak (107) and Kota Tinggi, Johor (106).

Fifty-two areas recorded “moderate” API readings of between 53 and 100, and two areas – Balik Pulau, Penang, and Langkawi, Kedah – had “good” readings of 39 and 33, respectively.

API readings of between zero and 50 are categorised as good, 51 to 100 as moderate, 101 to 200 as unhealthy, 201 to 300 as very unhealthy, and 301 and above as hazardous.