New developments after that train derailment in East Palestine, Ohio.
The NTSB chief said Sunday that the agency is not satisfied with the new safety goals outlined by Norfolk Southern and that community is still reeling from the toxic spill in February.
The head of the NTSB with tough words for embattled train operator Norfolk Southern and its new safety goals.
"They are not robust enough. I think we'll be looking at more recommendations as part of our investigation," said Jennifer Homendy, National Transportation Safety Board chair.
The train operator is under investigation amid a series of train derailments in recent weeks, including the one in East Palestine, Ohio, one in Alabama, as well as one in Springfield, Ohio -- after which an internal inspection revealed that some Norfolk Southern rail cars had defective, loose wheels.
The NTSB's chairwoman said more testing and changes are on the way.
RELATED: Ohio toxic train derailment: EPA vows to support East Palestine as rail company handles cleanup
"In fact, just this week, we will be doing testing of the pressure relief valves that release that are in charge of releasing pressure of those five vinyl chloride 10 cars," Homendy said.
Those safety valves now part of the NTSB's probe into the train derailment and chemical spill in East Palestine, Ohio, back in February.
Saturday, residents just outside of East Palestine protested, holding up signs that read "Norfolk needs to pay."
"We're here to tell them that they need to step it up and do the right thing, and norfolk needs to be held accountable.
RELATED: Norfolk Southern CEO to testify before Senate next week and 'share what he knows' about derailment
It comes days after senators on Capitol Hill pressed CEO Alan Shaw on paying for long-term damage and caring for the residents.
The CEO of Norfolk Southern will be back on Capitol Hill to testify in a hearing that will focus on rail safety. The NTSB's chairwoman will also be testifying during that March 22 hearing.