BART officials say that at the end of this year they expect to start testing on train cars with a small but crucial difference – an extra door.
The new Bombardier cars, the first of which should begin arriving in December, will include three doors, rather than the current two, to reduce crowding near the doors and allow passengers to get on and off the train more quickly.
"The issue we have today is that people are concerned they can't get off a crowded train, so they cluster near the doors," said Henry Kolesar, BART's group manager for vehicle maintenance, in a statement.
The change should also reduce the time needed for trains to get in and out of stations, BART officials said.
The new doors also have a different "microplug" design, more like that of the sliding door on a minivan than the current "pocket" doors, which slide into a space in the wall of the car. The new design should seal more tightly, reducing exterior noise, and break down less often, officials said.
BART will test the new trains for around a year and hopes to begin using them in passenger service by December of 2016, spokeswoman Alicia Trost said Wednesday. Testing will be conducted largely on test tracks and on regular tracks during out-of-service hours.
The bulk of BART's more than 600 cars date back to the 1970s and 1980s and are nearing the end of their useful life span, according to BART officials.
In 2012 the BART board voted to approve a contract with Bombardier for new cars. The agency has ordered 776 cars, at an estimated total cost of $2.5 billion, and has an option to eventually order a total of 1,081, Trost said.
The larger number of cars will allow the agency to run longer trains, increasing capacity.