Five contractors were sent to the hospital as a precautionary measure after a massive blaze broke out at a Shell chemical plant in the Houston suburb of Deer Park, according to ABC13. The fire, which began Friday afternoon, has now been contained, according to authorities, with Deer Park Mayor Jerry Bouton saying firefighters were in the process of burning off “burned carbon,” which does not pose a threat to the surrounding community. The plant produces light and heavy olefins, as well as phenols, chemicals used in the manufacture of everything from plastics to pharmaceuticals and antifreeze. “We don’t know the cause of the fire, but a Harris County Fire Marshal investigation will begin as soon as the fire is out,” said a precinct commissioner with the Harris County Pollution Control.