An ammonia leak forced 100 employees to evacuate a warehouse early Tuesday morning in Prince George’s County.
Investigators said a pipe began leaking anhydrous ammonia at the Smithfield Packing Company in Cheverly, Md., at 12:15 a.m.
The chemical is used in industrial refrigeration applications. It is a colorless, highly irritating gas with a sharp, suffocating odor.
It took four hours to fix the problem.
Seventy firefighters and Hazmat teams responded to the call.
No injuries were reported.