The design of the burner nozzle allowed the nozzle swirl plate and needle valve to be misaligned when being assembled which in turn led to the needle valve stem being damaged during assembly. Furthermore, the maintenance manuals and supporting documentation supplied by Garioni Naval, the thermal oil heater manufacturer, did not provide sufficient guidance to ensure safe and appropriate maintenance of the thermal oil heater burner assembly.
Increased awareness will assist in assessment of the issues involved and contribute to safety actions which reduce the risks with this equipment. Dialogue and awareness are necessary steps towards achieving an engineering solution to the issue.
The ATSB has been advised by Garioni Naval that the company has made enquiries and contacted several manufacturers of burner equipment to discuss the incident and burner design. Specifically, Garioni Naval contacted the original manufacturer and supplier of the burner equipment involved in this incident seeking detailed information.
However, to date, the design of the burner nozzle has not changed. The ATSB has also been advised that Garioni Naval is in the process of updating its equipment manuals to highlight the importance of correct burner nozzle assembly and alignment of its component parts.
The ATSB notes that, to date, the design of the burner nozzle has not been changed, but acknowledges that increased awareness of the risks associated with the maintenance of the burner nozzle should reduce the likelihood of future similar incidents.
