On Oct. 10, 35 people were injured and two killed.
The new lawsuit is for the death of 28-year-old Jose Perez, who lost his life last month while working as a contractor at the Pemex facility.
His family is now suing Pemex and two other companies, saying his death was preventable.
The 30-page lawsuit was filed in Harris County alleging Pemex, Shell USA, and PMI Services of North America were negligent after 35 people were injured and two killed in a chemical leak last month at the Pemex refinery in Deer Park.
"(The families) can't get their loved ones back. What they want is changes so that this never happens again. This was an absolutely preventable event if folks would have followed procedure and safety rules," Managing Partner at Abraham Watkins Law Firm, Benny Agosto Jr., said.
Attorney Benny Agosto Jr. is representing the Perez family. He says Perez was in an adjacent unit when the release happened. He tried to escape but passed out before he could get out.
Agosto says they've investigated the Pemex site with their engineers.
"There was a work order that was not done properly. When you do work permits, you have to walk contractors out there. Contractors that started working on this pipe, that was not isolated. (It) was opened up, and poisonous gas came out," Agosto said.
The lawsuit accuses Pemex, PMI Services, and Shell USA of a laundry list of violations, including failure to implement safe evacuation procedures and improper maintenance of equipment.
ABC13 has reached out to all three companies being sued and is awaiting a response.
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