On the night that a Norfolk Southern train carrying hazardous materials derailed in East Palestine, Ohio, it took nearly an hour for some first responders there to find out what chemicals were onboard.

That was one of the revelations made public on Thursday, the first of two days of hearings in East Palestine held by the National Transportation Safety Board on the Feb. 3 derailment involving the Atlanta-based railroad.

Emergency responders were trying to get a record known as the “train consist” — which lists the rail cars and their order in the train — as the fire from the derailment blazed, firefighters responded to the scene and first responders considered evacuating residents.

Ultimately, the derailment led to one of the biggest evacuations from a U.S. rail accidents in years. State and federal officials have indicated the air and water are safe. But there are residents in the area that have fears about the long-term impact of their health from the chemicals released including vinyl chloride, which in the long term with severe exposure can cause several cancers.

“The train derailment has quite frankly changed East Palestine forever, has disrupted lives, impacted businesses and created uncertainty,” said East Palestine fire chief Keith Drabick during his testimony.

NTSB Chair Jennifer Homendy said it’s rare for the agency to hold field hearings, but the decision was made to hold the proceedings in East Palestine instead of in Washington, D.C., because “the people affected by this derailment deserve as much insight as possible” and “so members of the public can hold the NTSB accountable for conducting a fair, thorough and independent investigation.”

“The information learned during this hearing will help us determine what went wrong on Feb. 3,” Homendy said. “We’ll then make safety recommendations to prevent similar derailments from ever happening again. And we’ll advocate for our recommendations for as long as it takes.”

Norfolk Southern, which has its headquarters in Midtown Atlanta, said it has taken actions to improve its safety culture. The railroad has also committed to helping East Palestine bounce back from the incident, working to remove contaminated soil and water, and to date has committed more than $62 million to the area.

During the hearing, Homendy questioned Scott Deutsch, a regional manager of hazardous materials for Norfolk Southern, asking him to explain why it took some time to get the train consist to some firefighters who had to figure out what kind of fire they were facing and how to protect their crews. The company faces multiple lawsuits over the derailment.

Deutsch said he was not aware of calls to the Norfolk Southern dispatch center, but that he sent a consist to a county emergency management agency director while he was en route to the scene.

He acknowledged, “It is a railroad’s responsibility to provide that train consist.”

It’s one of a number of communication issues that arose in the frenzy in the dark of night in East Palestine, with police, multiple dispatchers and fire departments and the railroad rushing to respond to the disaster.

Drabick, the fire chief, testified during the hearing that he “absolutely” has concerns about the impact of the burning chemicals on the health of his firefighters.

“I started voicing those concerns shortly after my arrival on the night of the incident,” Drabick said. “I’m concerned about not only my responders but everybody around for long-term health concerns.”

The NTSB conducts accident investigations and makes safety recommendations, but does not have authority to regulate railroads nor to enforce its safety recommendations. Instead, it pushes other federal agencies and companies to adopt the safety measures its recommends.

Among the issues the NTSB is tackling at the East Palestine hearings is the need for more training to prepare firefighters to deal with hazardous materials.

It’s particularly challenging to get adequate training for volunteer fire departments, including those that responded to the East Palestine derailment, which already struggle to maintain enough volunteers and funding to meet their needs, witnesses testified.

Most fire departments in the U.S. operate as volunteer fire departments, said Drabick, who pushed for more federal funding for training. “Every community in this country needs to have (those) emergency services ... fire, police and EMS.”

The NTSB hearing also focused on detection systems, tank car derailment damage, hazardous materials information and the circumstances that led to the decision to burn five rail tank cars of vinyl chloride.