Geismar , Louisiana ( CNN ) -- A second man has died as a result of Thursday 's explosion at a Louisiana chemical plant , the Louisiana State Police said Friday . Scott Thrower , 47 , of St. Amant , died at a Baton Rouge hospital after suffering burns in the blast at the Williams plant in Geismar , state police trooper Jared Sandifer said . The Thursday morning explosion killed one other worker and injured more than 100 others in what company CEO Alan Armstrong characterized Friday as `` a terrible and unprecedented tragedy and an extremely difficult time for all of us . '' Before Thrower 's death was announced , the company said six people -- two employees and four contractors -- still were hospitalized Friday . Their conditions were n't available . The explosion at the plant , which Williams says produces about 1.3 billion pounds of ethylene and 90 million pounds of polymer-grade propylene each year , sent a plume of thick smoke into the air and initially forced authorities to ask people nearby to stay inside to avoid exposure to potentially toxic fumes . Investigators still were waiting for the plant to be safe enough to investigate the blast 's cause , officials said Friday . Armstrong told reporters Friday that the incident was tough to take . `` A lot of us in this industry have spent much of our careers working to make it safe to operate , so when something happens like this , honestly it feels like a big failure , '' Armstrong said . `` I would tell you we 're very committed to returning to a safe operation , but this industry works extremely hard to make these operations safe , so it 's very , very disheartening when something like this occurs . '' A dramatic image provided to CNN affiliate WAFB by a plant worker who did not want to be identified showed workers running from a towering orange column of flame ripping through part of the plant on Thursday . The fire has since been extinguished . The plant had a minor propylene leak Friday , but the chemical vaporized as it came out , Sandifer said . The state Department of Environmental Quality and Williams-hired air monitoring contractors are checking the site , and air-quality tests so far have found nothing concerning , he said . `` There is no threat to the public of any toxic chemicals being in the air , '' Sandifer said . Authorities lifted a shelter-in-place order for people in the area Thursday afternoon . Three employees and 100 contractors received medical treatment after the blast . More than 830 people were at the site -- more than usual , because of a plant-expansion project , plant manager Larry Bayer said Friday . Bayer said the blast happened in the plant 's propylene fractionation area , but said he did n't know what led to the explosion . `` We have been waiting for the last amounts of residual hydrocarbons to escape from the ... piping through the night . An investigation to determine what happened is still pending and will begin as soon as our team is allowed to go back into the plant by the state police , '' Bayer said . About 25 workers were in the facility 's control room Friday to monitor the situation , but the plant has effectively shut down , company officials said . The first worker who died , killed 29-year-old Williams employee Zachary Green , joined the company in October . Williams officials met with his family at their home Thursday , the company said . `` We are grieving for the loss of Zack , who was part of our Williams community , '' Armstrong said in statement Thursday . `` Our thoughts and prayers are with the family at this time of sorrow . '' CNN 's Jason Hanna contributed to this report .
Thursday 's blast at Williams chemical plant in Geismar also injured more than 100 . CEO : We work for years on ensuring safety , so this is hard to take . Police : `` No threat to the public of any toxic chemicals being in the air '' we are working with authorities and will continue our investigation into what caused it.