Masks are hard to prevent dust and smoke effectively

According to UPI, masks are a popular item in many cities in Asia, where people have to deal with serious air pollution. However, according to a team at the University of Massachusetts Amherst, USA, the most popular masks have limited protection against harmful dust.

People in Beijing, China, use masks to combat air pollution.(Photo: Stephen Shaver).

The team's results showed that the most expensive fabric masks prevented 65% of large-sized dust particles, but they could not help wearers avoid particles smaller than 2.5 micrometers. The popular cheap masks in Nepal, China, India and many Southeast Asian countries have poor protection.

"Facemasks help us reduce continuity with airborne dust to a certain extent. But commonly used masks have poor protection performance," the authors conclude in an article published on August 18 on Journal of Exposure Science and Environmental Epidemiology.

Richard Peltier, the lead author of the study, said the mask gives people a sense of false security, giving them confidence when coming to places that are seriously polluted.

"Millions of people wear masks and they feel safer. But masks cannot protect them from emissions from diesel trucks right next to them , " Peltier said.