5 Yearly Hydrostatic Test {are you testing the tanker vapour coaming?}
In a recent incident at an Australian fuel terminal gantry, a driver attempted to load a tanker compartment that had already been loaded.
This error by the driver resulted in an estimated 10 litre spill, the tanker/gantry overfill protection system was activated and closed the gantry loading system. However due to an incorrectly installed overfill protection probe in the compartment, this error led in a failure to contain the product within the compartment. As a consequence, product entered the vapour recovery vent, pipework and coaming rail. Normally if this were to occur the product would be contained within the vapour system. In this incident however product leaked from the vapour coaming via small holes drilled at various points along the vapour coaming.
Thankfully no one was injured, and no equipment was damaged.
Direct Causes
- The tanker overfill protection system probe was not set to industry minimum safe fill ullage requirements.
- The driver understood but did not follow loading procedures.
- The tanker rollover/vapour coaming had holes in it when purchased by the current owner, the holes were not known or identified by the owner as a problem.
- The tanker had been tested and certified on (5) five previous hydrostatic tests conducted by (4) four different maintenance/inspection businesses.
Recommendations
- Prompt industry to ensure they are hydrostatically testing the tanker vapour pipework and coaming rail at (5) five yearly hydrostatic testing events.
- At (5) five yearly Hydrostatic and 2 ½ yearly Hatch & Vent testing events, maintenance and inspection businesses must ensure overfill protection system probe heights are set in line with industry minimum ullage requirements.
- Tanker owners must ensure they are provided with documentation that confirms their tanker vapour system has been hydrostatically tested during the (5) five yearly inspection.
Lee Stringer
SLP Manager
