Due to an incident that took place on February onboard Sydney Harbour operating passenger ferry in which a high level of toxic gas was detected in a toilet cubicle after a passenger was fatally injured, the importance of maintaining chemical toilets is at the core of the attention.
Specifically, the incident regards a 39-year-old passenger that was found unconscious in a toilet cubicle aboard the Lady Rose and could not be revived by paramedics.
Although the reasons leading to her death are unconfirmed, during the initial investigation HAZMAT crews detected hazardous levels of hydrogen sulphide gas in the toilet cubicle.
According to a New South Wales Police report:
Investigators were advised that several gas detection tests were conducted in a bathroom area of the vessel and were found to be in excess of safe operating levels.
In light of the incident, Mark Beavis, Managing Director, ACO Marine, informed passenger vessel operators of the fatal consequences of hydrogen sulphide escaping from poorly maintained onboard sewage systems.
He, furthermore, commented:
This dreadful story serves to highlight the issues of poorly maintained chemical toilets and poor or obstructed ventilation in these small toilet cubicle spaces.
According to Mr Beavis, some small passenger vessels don’t have installed treatment system and they keep the wastewater in holding tanks. Yet, if the latter is not often flushed and aerated the contents can become anaerobic and generate lethal H2S gas.
Generally, Mr Beavis supported that one simple way of protecting passengers from the hazardous gases generated from untreated effluent is to ensure that all bathrooms and toilet cubicles are fitted with sensors.
According to the Managing Director, sensors with integrated alarms on the bridge would allow for more immediate action in the event of any hazardous gas leaks and the integrity of the seal between the cabin space and the wastewater holding tank should be checked regularly.
The Australian Maritime Safety Authority and New South Wales Police continue to investigate the incident.
Concluding, hydrogen sulphide is a gas produced during the decomposition of waste. In modest concentrations of between 700 and 1000ppm it is toxic and can lead to sudden collapse and death, according to the Occupational Safety and Health Administration (OSHA).
