"I stayed focused on placing the face masks on the machine one by one and the tempo had to be accurate," he says.

Guo was among 15 volunteers from the orchestra to work at the factory on March 25.

They worked the night shift and made a total of 44,000 face masks on that day.

According to Zhou Ping, president of the orchestra, who also put in a shift on the production line that night, all of the volunteers had their temperature checked and were disinfected before entering the factory.

Since the entire production process was mechanized, volunteers were divided into groups and were given different tasks, from checking the quality to the final packaging.

"Because of the viral outbreak, the country faced a severe shortage of face masks. In the middle of the coronavirus pandemic, we want to offer our help. Volunteering at the face mask factory is one of the most direct and efficient ways of helping," Zhou says.