SAN FRANCISCO—Bay Area Rapid Transit (BART) received 10,000 disposable face masks from Shanghai Metro on Tuesday, June 9. On Wednesday, June 10, BART indicated that those masks will be used for their workers and customers via Twitter.

Shanghai Metro is a rapid transit system in Shanghai, China, which opened in May 1993. It is the second biggest metro system by route length in the world. Shanghai Metro is a member of the Community of Metros (CoMET).

In 2012, BART started developing a “Sister Transit Agency” affiliation with Shanghai Metro. In 2014, the BART Board of Directors approved a Memorandum of Understanding (MOU) for the development of the “Sister Transit Agency.” The move aimed to benefit both the transit systems and the riders by sharing ideas and experiences. BART could acquire knowledge about Shanghai Metro’s Bombardier manufactured train cars which would help them improve on their own trains.

Currently, BART is working on implementing the 15-step plan as the city of San Francisco gradually reopens. As the fifth step of the plan notes, BART asks all the riders to wear face coverings when they are in the stations or on the trains. BART also requires their employees to wear masks while on their shift. BART will give some of the extra masks from Shanghai Metro to the officers to hand out to the riders.

“Through thick and thin[sic] friendship lasts forever,” read a statement from BART via Twitter thanking Shanghai Metro in English and Chinese.