Copper/Silver Sterlisation Technique - A First for Autralasia

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If you work in Elizabeth Rothwell Building and you have noticed the hot water isn't quite so scalding hot as it used to be, then here's why. Legionella is a problem for many institutions around the world - hospitals, hotels, convention centres, large buildings of any sort are vulnerable to the bug which is mainly carried through their hot water systems.

For the most vulnerable hospital patients - including babies and the elderly - legionella is an unacceptable risk.

But the legionella bug is adept at avoiding usual methods of sterilisation. It doesn't get killed by chlorine. High temperatures combined with regular flushing of the system to keep it clean, is a labour intensive response that may also risk patient and staff being scalded by too- hot water.

Elizabeth Rothwell Building (ERB) at Waikato Hospital is a classic mix of older pipes and vulnerable patients - which is why it was targetted by engineer Gordon Peters and infection control nurse Carol Jarvis.

Linking in with Mark Dawson, representing Chicago-based company Liquitech Ine, they have come up with a solution that you could call "win-win-win". It means lower risk of water-born infection, lower risk of scalding, and lower energy costs.

The technology involved - copper/silver ionisation - is as old as the Roman Empire, but applying it in a controlled way to modern standards is a very recent development. In fact, this is the first use of the Liquitech system in Australasia.

It's not unproven, however. Mark Dawson says that over 500 hospital applications around the world have built up a proven record of success. The company has also installed the system in major hotels. But right now, at Elizabeth Rothwell Building, Gordon Peters and Carol Jarvis know it is still early days. The equipment was installed in August. Now the first round of actual water sample testing is taking place. The most dramatic impoct so far is that the temperature of the water. It has been lowered from a very hot 65 degrees centigrade to a safe 45 degrees, without compromising sterilisation.

Samples are being taken from taps and shower heads through Elizabeth Rothwell and sent to an independent lab for testing. This will be done on a regular basis - more often in the early stages of implementing the technology, and then at set intervals. On-going monitoring of the system is also provided through a smart control box that continuously reports on the functioning of the system. These reports can be accessed at any time, anywhere, by logging into the system via a Vodaphone cellphone link.

Carol first became aware of the copper/silver ionisation sterilisation technique some years ago during a visit to the United States. The technology was in its early days of development, but she has kept an eye out for its possible application ever since. Meanwhile across the campus in Engineering, Gordon got hold of a brochure about the technology, got curious about it, and did his own research into how it worked. "I entered the words into a search engine and couldn't believe the amount of information I came up with. I realised it was being applied in a lot of European and American hospitals, but yet to be used down here. Working with Carol, we put a case together to spend about $80,000 on it, but it's a real investment."

For Gordon, it will dramatically reduce the costs of maintaining the system and heating the 4000 litres of water Elizabeth Rothwell uses each day.

For Carol, it is an important step in keeping staff and patients in Elizabeth Rothwell safe from legionella.

Gordon and Carol hope that the system might be used in other areas of the hospital, but the age of existing pipes may be an issue. Building it into new buildings in the SCR project is something else they will be advocating, for both its energy saving and infection control advantages.

How Does It Work?

Liquitech's electronic liquid disinfection system releases copper and silver ions into the water by allowing it to pass through a flow cell containing sacrificial cooper/silver electrodes. A direct current is applied across these electrodes to stimulate the controlled release of ions. These ion emissions are a potent biocide. The positively charged copper and silver ions form electrostatic bonds with negatively charged sites on microorganism cell walls, creating stresses and distortions that, combined with protein denaturation, lead to cell lysis and death. In this system, bacteria are killed, rather than merely suppressed. The accurate dose-rate control system maintains precise ion levels, providing residual protection and prevention of recontamination.

How safe is your water?

A "Proactive" program is the wisest strategy. Eliminating serious infectious threats like Legionella, Listeria, Staphylococcus, Pseudomonas, etc. translates into healthier patients, a safer environment and reduced costs and exposure. Find out how.

More Information

American Water Works Association

Environmental Protection Agency

EPA Water Quality Standards

Partnership for Safe Water

JCAHO

LiquiTech adheres to and is registered by the United States Environmental Protection Agency.