The final investigative report into a fire and explosions at the Philadelphia Energy Solutions (PES) Refinery in Philadelphia, Pa., which occurred in June 2019, has been released.

The PES incident occurred when a corroded pipe elbow ruptured, releasing process fluid into the refinery’s hydrofluoric acid alkylation unit. During the incident, more than 5,000 lb of highly toxic hydrofluoric acid was released. In addition, a 38,000 lb vessel fragment launched off-site and landed on the other side of the Schuylkill River. In all, an estimated property damage loss of $750 million resulted.

The CSB also released its final report on the 2016 flash fire and explosion at the Sunoco Nederland, Texas, crude oil terminal, which resulted in burn injuries to seven workers. The CSB’s investigation identified deficiencies in the company’s hot work policies and procedures as well as the contractors hired to execute the work. The final report highlights key safety lessons learned from the incident at the Sunoco facility that can prevent future hot work incidents.