Headway offers reassurance after BWMS explosion
The company attributed the incident, which resulted in the ejection of the unit with enough force to damage nearby equipment and cabling, to negligence on the part of an authorised Headway service engineer. The engineer forgot to exit test mode and reboot the system after conducting crew training. This led to a continuous current supply to the electrocatalysis and ultrasound unit (EUT) with both inlet and outlet valves closed, eventually causing the failure.
In a safety alert dated 25 November 2016, the UK Health & Safety Executive (HSE) noted: “This unit incorporates electrodes that have the potential to operate under low or no ballast water flow during maintenance and calibration activities, overriding the flow sensors. Their operation may continue if the systems are not re-set.
“Under such conditions electrolysis and overheating is likely to continue to such an extent that the unit could fail catastrophically from overpressure and/or internal explosion in the absence of adequate over-pressure relief. Awareness of such a developing situation will be difficult in the absence of temperature and pressure indication.”
In a technical circular in late January, Headway advised its customers of the incident and offered a free upgrade to prevent reoccurrence if the system is left in test mode. It also committed to providing free annual inspection for all delivered systems to ‘eliminate any potential risks that may be caused by idle system after long time’.
In a statement the company said: “Upon notice of the failure, Headway started a deep investigation and analysis into the root cause, with the support of ship owner, DNV GL, HSE… This incident has reminded Headway that not only the system failure and [misuse] by ship crew should be considered during the design of safety functions, but also the misconduct of authorised engineers.”
The OceanGuard system uses electrochlorination to neutralise organisms in ballast water and sediments. The HSE warned users of similar systems of the need for thorough risk assessment, noting: “Operators that use these and similar units, or are planning to install them, should undertake a suitable and sufficient assessment of the risks from using the equipment, such as via a detailed HAZOP study.”
NOTE: Headway Technology’s OceanGuard system is entirely unrelated to the systems provided by Danish ballast water management specialist DESMI Ocean Guard.
