Yacht crews should be monitoring potable water more frequently to avoid Legionnaires, says CMT
by CM Technologies 11 Feb 11:05 GMT
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An AI-generated image of Legionella testing aboard a superyacht © CM Technologies
Germany-based system monitoring specialist CM Technologies (CMT) is advising superyacht managers to carry out more frequent testing of potable waters onboard their craft following a spate of outbreaks of Legionnaires' disease on passenger ships.
Recent incidents have highlighted the dangers of neglecting water system maintenance and testing on super yachts, with spas and pools being flagged up as particular areas of concern.
"Hot tubs are a real problem," explained, CMT's Managing Director David Fuhlbruegge. "Most yachts have them these days, with operating water temperatures of between 37 degreesC and 40 degreesC which is the ideal environment for both bathers and Legionella bacteria."
He explained that while the pathogen survives in temperatures between 20 degreesC to 45 degreesC, the smaller volumes of water used in hot tubs can increase the risk of Legionella growth, which can be spread more rapidly with aeration and water mist.
Referring to a Legionella risk assessment CMT carried out recently onboard a yacht berthed in Barcelona, Spain, Fuhlbruegge said "it was a real eye-opener the extent of the problems they were having."
He also revealed a number of incidents where owners, passengers and crew aboard a mega-yacht were at risk from Legionnaires' disease and another incident where several guests contracted gastrointestinal illnesses after consuming contaminated water while cruising. There was also a recent case where a super yacht was forced to cancel a charter after an outbreak, costing the owner dearly in lost revenue.
"These are not isolated incidents," he said. "But the financial implications of water contamination can be devastating. Waterborne pathogens like the Legionella bacteria and other faecal-type bacteria such as coliforms, pseudomonas, enterococci, cryptosporidium, and E.coli pose an ever-present risk that requires vigilant monitoring and management. Managers and crews need to treat this as a top priority."
Fuhlbruegge furthered that the temperature of water storage tanks also requires vigilance, especially when operating in warmer climates. Water should be stored under 20 degreesC and distributed above 55 degreesC. But the problem is tank temperatures often exceed this temperature due to the yacht's operational profile.
Advocating more frequent testing than the "regular" testing mandated by regulations, Fuhlbruegge explained that traditional water testing methods are problematic in that they usually require sending samples to shore-based labs for analysis, which can take weeks before the results are returned, by which time there could be a serious outbreak and therefore too late to take preventative measures.
"Water quality can change rapidly, especially on super yachts that are constantly moving between different locations and environments. Owners need the ability to monitor in real time and not just once or twice a year," he said.
CMT's new Legionella Test Kit is deemed a breakthrough technology for the rapid detection of Legionella bacteria in marine potable water systems, as it delivers test results in minutes instead of days.
Optimised for use with hot and cold-water systems, the simple-to-use kit contains everything crews needed to perform tests onboard, delivering results within 25 minutes and without having to send samples to labs shoreside.
CMT's joint Managing Director Uwe Krueger, said: "Our new test kit reduces risk of Legionella outbreaks and any subsequent litigation, offering instant, on-site analysis that allows yacht crews to easily identify and address issues before they become a crisis. Frequent, automated testing is key.
"Super yacht crews should be checking parameters like bacteria levels, disinfectant concentrations, and heavy metals on monthly, if not weekly basis. This allows crews to spot trends and take corrective action before problems spiral out of control.
"Simple regular assessment and testing of the potable water system for microbiological activity, biocide (disinfection control) and implementing a correct control scheme (i.e. temperature monitoring), will ultimately reduce the risk of a disease and save lives," Krueger added.
The CMT Legionella Industrial Water kit forms part of a range of new onboard water testing, analysis and incubation kits, designed to assure owners, managers, passengers and crew that the potable waters produced and stored onboard their yachts are always fit for purpose.