In June 2013, Southeast Asia was blanketed by thick clouds of haze arising from wildfires in Indonesia.

A Singapore study surveyed participants in a large residential district on their knowledge, perceived risk and behaviours during the haze crisis. The study found that knowledge of haze was associated with protective behaviours, while a lower education level and smokers were associated with lower knowledge. Wearing of N95 masks correlated with other protective behaviours and did not lead to a false sense of security. The insights gained to encourage adoption of protective behaviours may be applicable to urban populations facing haze problem and even infectious disease outbreaks like the COVID-19 pandemic.