According to CBS:
WILMINGTON, Del. (CBS) — Emergency crews responded to a hazmat situation Saturday at a research and development facility in New Castle County, Delaware.
It happened around 11 a.m. at the DuPont Experimental Station along the 200 block of Powder Mill Road in Wilmington.
Officials said 18 workers there became exposed to an unknown substance while contractors were conducting remediation work in a lab at the station.
An emergency response team was already on site and quickly responded, along with first responders from New Castle County.
Authorities says all of the workers were removed from the building and sent through a decontamination area. They were then taken to local hospitals for evaluation.
DuPont officials did not immediately confirm what type of material the workers were exposed to, but said there was no threat of exposure to the community.