A chemical safety expert says light gray smoke coming from the controlled burn of highly unstable compounds at a Houston-area chemical plant likely shows harmful elements are burning off.
Sam Mannan from Texas A&M University says the thick black smoke in previous, unplanned fires at the Arkema plant in Crosby, Texas, showed organic peroxides being stored in trailers weren't fully combusting. Fire officials and the company warned people not to inhale the smoke because it could make them sick.
Mannan says a proper burn-off leaves behind only carbon dioxide and water, creating a light gray smoke.
Arkema had said Harvey floodwaters engulfed the plant's backup generators, knocking out the refrigeration necessary to keep the peroxides from degrading and catching fire. In recent days three trailers had ignited, sending thick black smoke and tall flames into the air.
