Metro is planning to install glow-in-the-dark signs on its trains this spring telling riders to stay onboard in case of an emergency.

The signs come after January's Green Line meltdown, when hundreds of riders self-evacuated from hot, stuffy trains after they lost power in a tunnel under the Anacostia River.

"In the event of an emergency, stay on the train and listen for train operator instructions," is written on the signs. "If an evacuation is necessary, be prepared for the dangers of low lighting, high voltage, uneven surfaces and moving trains."

Metro officials focused on the self-evacuation as the No. 1 problem in the Green Line incident and were looking for a way to prevent it from happening again.

"The thing that magnified it the most was the self-evacuation. ... If people can stay on the train, then we'll get them out much faster," General Manager Richard Sarles said earlier this year. "When you go out on those tracks, you don't know if you're going to hit a live third rail."

Metro is also developing new onboard signs with more emergency instructions, saying in documents that its current signs near rail cars' center doors are "text heavy," with "unnecessary maps" and "unreadable in emergencies."

"It's pretty busy," said Metro Assistant General Manager Lynn Bowersox. "It doesn't really articulate in a clear and evident way that your first instinct should be to stay on the train unless you hear instructions to do otherwise."

The new signs come as Metro prepares to launch its "Ride Safe" advertising campaign this month, at a cost of about $100,000, with posters warning riders not to hold train doors, stand on the edge of station platforms or walk in front of buses.

Metro plans to put 114 posters in station entrances, 1,118 in rail cars, and 3,400 in or on buses.

Metro staff hope the safety campaign will help them reduce their customer injury rate by 5 percent over the next year. About 580 Metro customers were injured last year, Bowersox said, and the agency is aiming for 29 fewer incidents this year. Most injuries on the system are slips, trips and falls, the agency said.