The Autism Transit Project has expanded to four more cities, the organization announced Wednesday. 

Launched in New York City last April during Autism Awareness Month, the campaign taps autistic children to record the public service announcements broadcasted on city trains and platforms. 

Jonathan Trichter, co-founder of alternative education provider Foundry Learning Center and CEO of special needs early education school Happy Hour 4 Kids, conceived of the campaign when he learned that autistic children commonly develop intense focus and fixation with uses of mechanical engineering that are common in their everyday lives. 

After posting a call to action on a local Facebook group for parents with special needs kids, he organized the campaign solo after more than three dozen families responded to his requests. 

Now, he brought the effort to four new cities, including the Bay Area’s BART, Atlanta’s MARTA, Washington D.C.’s WMATA and the New Jersey NJ Transit, as well as returning to New York City’s MTA. 

“For whatever reason, children with autism tend to be drawn to subways, and frontline transit workers are well familiar with that phenomenon,” Trichter told Campaign US. “They see it every day when these kids are dragging their parents on joy rides to nowhere or asking them very complex questions that stump them about the system and its repairs and changes.” 

As a result, it’s not uncommon for a neurotypical child’s first words to be “stand clear of the closing doors please,” he explained, as autistic children often repeat phrases or words they hear a lot or like. 

To expand the campaign to new cities, Trichter again took a grassroots approach, using social media to recruit local train-loving kids and working directly with the executive teams at local transit service organizations. In New York, he worked with the MTA through a new partnership with Include NYC, a disability advocacy organization.  

“I took some of the press clippings we got around the project in New York City and sent them to a bunch of transit agencies in large American cities and got acceptance responses [right away],” he explained.

After selecting more than 100 families to participate, Trichter recorded the announcements himself with help from transit workers and executives. They will run throughout the month of April. 

Next year, Trichter has ambitions to bring the campaign to cities in other countries with major transit systems like Tokyo, London, Paris and Berlin. 

“I am particularly set on that goal because there are other countries with state-of-the-art mass transit systems, but mixed histories when it comes to treating their disabled communities equitably,” he said. “A lot of those countries’ leaders recognize that history and are trying to modernize and be more inclusive.” 

For now he hopes the campaign opens up people’s perspectives and builds their empathy toward the autistic community each time they hear a child say, “Stand clear of the closing doors, please!”

This article originally appeared on Campaign US.