According to a December 2016 report by the European Center for Disease Prevention and Control, an increase in cases of Legionnaires’ disease compared with previous years was reported in EU travellers returning from Dubai. Twenty-six cases were reported with the onset of illness on 1 October 2016. However, the report further stated that “it cannot be ruled out that these travellers might have acquired their infection elsewhere than in Dubai, if their travel stay was shorter than the range of the incubation period”.
Mark Engelenburg, CEO of the Netherlands-based company ATECA, says copper-silver ionisation is the best technique in preventing Legionella outbreak and other bacteria.
Copper-silver ionisation is a disinfection process, primarily used to control Legionella, the bacteria responsible for Legionnaires’ disease (legionellosis). Engelenburg says: “The knowledge of copper-silver ionisation to fight bacteria has been around for several years. Think about fountains or water wells with copper and silver coins in them. Originally this was to prevent the water supplies from decaying. In addition, silver cutlery and cans were known to reduce bacteria growth and thus the risk of illnesses. Eventually, it was NASA that did extensive research on how copper and silver act on bacteria in water. They found it to be extremely effective, especially on legionella, and used the technique of copper silver ionisation to keep their water safe. It was not long after we were able to design a system that was to be used for potable water installations in buildings, cooling towers and swimming pools.”
Engelenburg goes on further to explain the process. “For potable water, we place the copper-silver ionisation system after the water metre of the water supplier. This means, it should be as far upstream as possible, and this gives the ions maximum time to be effective. Here, in the UAE, copper-silver ionization systems are sometimes placed in the circulation line of the tank. This also works, although it is a little more complicated to control the exact dosing of the ions.
“The treated water in the tank will then be distributed into the building (hotels, malls, hospitals, etc). Fortunately, copper and silver ions are always positively charged, while waterborne pathogens like Legionella are negatively charged. Therefore, the ions and bacteria attract each other and the reproduction [of bacteria] will be stopped. It will be just a matter of time after which you will flush out the bacteria activity. To be more precise, the copper will open up the cells in the bacteria, and the silver ions will enter and stop the reproduction of bacteria.”
There are different types of copper-silver ionisation systems used for different applications. “It should be obvious that a system designed for use in a swimming pool has different requirements than a copper silver ionisation used for a potable water system. Potable water requires a much higher level of safety, which means absolute precise control of copper-silver levels and the use of non-toxic materials. In a swimming pool, people are not consuming the swimming pool water. The same goes for cooling towers. So installing a swimming pool system for a potable water application is never a good idea,” Engelenburg says.
Choosing the right system
One must choose a system that is designed for the actual application you are using it for. Engelenburg recommends choosing an experienced and trusted supplier. He says: “These systems need maintenance and electrode replacements. It’s very unfortunate to find out that you can’t get any replacement electrodes or that there is no help when your system malfunctions.
“What we at ATECA find a very important aspect is monitoring. Our experience here in the UAE is that there is not a lot of attention given to it. It should help facility managers as monitoring makes his or her life much easier and it simply saves man hours. Our monitoring system, for example, just needs an internet connection; the client can login from anywhere, anytime and he/she can see the status of the system and the electrodes, adjust the settings, look into the logs and so on. It can also send automated notifications for maintenance and changing electrodes. To summarise, systems with a monitoring option are safer and much more efficient.”