Bangkok’s neighbouring province of Samut Prakan has been ranked having the world’s 9th worst air quality. The place has not enjoyed a single day of good air quality in 12 months, according to House Fresh, a publication focused on air quality.

House Fresh offers advice on how to tackle air pollutants in the home through how-to guides, product reviews, advice and original research on a variety of factors that affect indoor air quality.

House Fresh said on its website that it had analysed data of air quality indices in the world’s cities and ranked each of them, with the worst being at No. 1.

The ten cities with the worst air pollution are Baghdad in Iraq, Patna and Jaipur in India, Kampala in Uganda, Isfahan in Iran, Gandhinagar in India, Lanzhou in China, Samut Prakan and Chandigarh in India.

Australia has the best air quality in the world, with Perth, Wollongong, Sydney, Adelaide and Canberra having good air quality throughout the year. Other cities with the most good air days include Zurich, Reykjavik, Honolulu, Newcastle and Auckland in New Zealand.

Countries with the cleanest air include Switzerland, Iceland, the United States and New Zealand.