Underlying Causes
• A prior set of firewater hoses used, were spotted to be leaking when it was used with fresh water during the prior cleaning. These
were changed and a “new” water hose was used, which eventually ruptured. This hose was not proper for this operation and was
not in ideal condition. There was no record of hose inspection available.
• Although the contractor at the manhole was using a chemical suit, he did not wear the suit hood and this allowed the caustic soda
to seep into the suit and contact his skin during the hose rupture. The suit was also not completely closed. The weather then was
40 degree Celsius His supporting worker, who was also exposed, was only donning basic PPE. Therefore, the risk from the caustic
solution was not fully recognized by the workers. No checks were done to ensure they followed these requirements. The risk
assessment done prior permit approval also did not recognize this hazard well.
• Cleaning was done through jetting diluted caustic soda through the tank manhole and this inadvertently exposed the workers to the
hazards of the caustic soda.
• There was a Safety Supervisor at site during the job. However, he was not fully aware of the need for proper donning of PPE during
the job. There was also no toolbox talk or Last Minute Risk Assessment (LMRA) before the job to highlight this hazard. The proper
handling of diluted caustic soda was also not made clear
• The job was approved through terminal’s Permit-to-Work (PTW) process. However, no proper site checks were conducted to
ensure workers were well donned in proper PPE. The permit was approved even while it was known that the firewater hoses were
leaking during prior cleaning with water. The risk assessment done prior to permit approval was also inadequate and not done in a
multi-disciplinary group.