PE classes in a bubble. This new stadium in Shijiazhuang keeps students safe from severe smog. Due to the regular air pollution in northern China, local authorities are restricting time spent outdoors for students.

To ensure that students still get their daily dose of exercise, this greenhouse-like stadium measuring 10,000 square meters can meet all kinds of sporting needs, from tennis to simple aerobics. Made of air-proof material, it is installed with an air ventilation system which keeps the air clean, even if pollution readings are off the charts. 

The stadium belongs to Huaxing primary school, located in Shijiazhuang city of Hebei Province. In the past year, the region has experienced less than 50 percent of days with good air quality.

According to Wei Chao, the engineer who maintains this stadium, the structure was affordable to build. It cost over three million yuan (436,000 US dollars), much cheaper than a conventional building with concrete walls. And it could be even cheaper, depending on the location in which it is built.

The bubble stadium is built to resist extreme weather conditions, such as strong winds, heavy snow and earthquakes, and it is fireproof as well.

Since it was built in 2016, almost every class has taken PE lessons in the bubble stadium every week. It is welcomed by parents of the students as they fear the air quality may harm their children.

While air pollution cannot be cleared up in a day, at least this will be a favorable, alternative solution for now.