The clients, many of whom are long-term partners and good friends of Dasheng, all agreed with the request for delayed delivery, "and we finally could catch our breath", Wu said.

Dasheng is now focused on the production of three types of surgical masks for both clinical and daily use. Aside from maintaining strict quality control, Wu also decided to add three more automated assembly lines and recruit about two dozen new workers.

"All our 163 workers but one, who is from Hubei province, will come back within a few days," he said. "We have no difficulty recruiting and training new workers, no problem with shipping and the raw material supply is normal and stable. We will not raise the price of the products," Wu said.

"I am not a learned man, but as a Communist Party member and army veteran, I am a patriot and Dasheng is just a drop of water in China's ocean of private enterprises."

Dasheng was one of the first surgical mask makers to have resumed production during the Spring Festival holiday. Another 16 companies in the metropolis also soon joined in the campaign to help relieve the shortage of medical supplies.

According to Liu Ping, head of the healthcare and manufacturing sectors at the Shanghai Municipal Commission of Economy and Informatization, the city produced more than 400,000 masks every day before the Chinese New Year, and, by Jan 27, daily output had increased to 800,000.