Legionella Prevention

Legionella prevention for hot & cold water systems

Legionella has been identified as a major problem in multi-occupancy buildings such as hotels, hospitals, hostels, schools, military establishments, nursing homes and office blocks.


ECA solutions help preventing the appearance of this bacteria, without risking anyone’s health or being costly.


Worldwide thousands of people become seriously ill or die through infection by this potentially deadly disease.
The costs if a building's water system becomes infected can be substantial not only in terms of human suffering but also financially. If a hotel is identified as a source of infection it can result in forced closure whilst the problem is treated plus possible lawsuits if people are infected. This means substantial loss of revenues and reputation. In addition, in many countries, if it is shown that the problem occurred due to the negligence of the hotel or ship operators and staff it can result in large financial penalties or even prison sentences for the individuals concerned. Every year hotels throughout the world are forced to close due to this problem often in the height of the tourist season. Every year people die in hospitals not from the disease that they were being treated for but from infection by this deadly bacteria that they contracted from the hospitals' water system. Due to the soaring price of energy, many operators of these buildings reduce the overall temperature of the hot water system which can increase the risk of infection by the Legionella bacteria.




Legionella tests - Anolyte

ENAC is a private, non-profit, independent Spanish organisation, supervised by the Ministry of Science and Technology and responsible for accreditation in the Spanish market.

The results of the laboratory tests carried out prove that even Legionella can withstand the Anolyte for only a few minutes. Within 10 minutes Legionella is reduced from 5 log10 to 0.

Test protocol Microorganisms Concentration cfu/100ml Time / minutes
  E. coli 1,5 x 105 1, 5, 10 and 30
  Salmonella spp. 1,3 x 105 1, 5, 10 and 30
  Pseudomonas aeruginosa 1,1 x 105 1, 5, 10 and 30
  Legionella pneumophila 1,5 x 105 1, 5, 10 and 30


Test 1              
Anolyte Parameter Units Start values 1 min. 5 min. 10 min. 30 min.
  pH Unit pH 81 81 81 81 80
  Residual chlorine Units mg/l 07 07 07 07
  Potential Redox mV 825 - - - -
  E. coli cfu/100ml 1,5×105 0 0 0 0
  Heterotrophic bacteria cfu/ml < 1 - - - -


Test 2              
Anolyte Parameter Units Start values 1 min. 5 min. 10 min. 30 min.
  pH Unit pH 81 81 81 81 80
  Residual chlorine Units mg/l 07 07 07 07
  Potential Redox mV 825 - - - -
  Salmonella spp cfu/100ml 1,3×105 NEG NEG NEG NEG
  Heterotrophic bacteria cfu/ml < 1 - - - -


Test 3              
Anolyte Parameter Units Start values 1 min. 5 min. 10 min. 30 min.
  pH Unit pH 81 81 81 81 80
  Residual chlorine Units mg/l 07 07 07 07
  Potential Redox mV 825 - - - -
  Pseudomonas aeruginosa cfu/100ml 1,1×105 POS NEG NEG NEG
  Heterotrophic bacteria cfu/ml < 1 150
< 1 < 1 < 1


Test 4              
Anolyte Parameter Units Start values 1 min. 5 min. 10 min. 30 min.
  pH Unit pH 81 81 81 81 80
  Residual chlorine Units mg/l 07 07 07 07
  Potential Redox mV 825 - - - -
  Legionella pneumophila cfu/100ml 1,5×105 1200 200 < 1 < 1
  Heterotrophic bacteria cfu/ml < 1 1200 200 < 1 < 1


ECA stands for electrochemical activation and is a technology that has been employed for more than 100 years, although it was not until the 1970s that the physicochemical properties of ECA were extensively researched at the All-Russian Institute for Medical Engineering.

The transformation of low mineral salt solutions into an activated metastable state, by electrochemical unipolar action, generates two separate and distinct compounds, generically termed anolyte and catholyte which correspond to their derivative electrode chambers:

  • The anodic (positive charge) solution contains a variety of oxidants, including hypochlorous acid, singlet oxygen, peroxide anion, superoxide, ozone, monoatomic oxygen and free radicals, known to possess antimicrobial properties
  • The cathodic (negative charge) solution develops detergent properties, contains sodium hydroxide in a highly excited state

The use of electrolysis for the production of reductant-oxidant solutions is used in the processes of water purification and decontamination, as well as for transforming water or diluted electrolyte solutions into environmentally friendly anti-microbial, washing, extractive and other functionally useful solutions.

This is largely due to ECA high activity, use of cheap raw materials and ease of production.

The system produces a liquid disinfectant, non-toxic and degradable, capable of destroying bacteria, spores, viruses, moulds, yeasts, fungi, biofilms (biological incrustations) on pipes and removing odours. Its operation requires only water, Sodium or Potassium Chloride (salt) and electricity.



ECA works the same way as the human immune system. When the body is under attack from invading bacteria and viruses, the immune system immediately responds by sending neutrophils (white blood cells) to the invasion site.

Neutrophils are one of the body’s main defences against bacteria and, once activated, produce large amounts of a mixed oxidant solution which is effective in eliminating invading microbes and pathogens.

This weak acid, which occurs naturally in the human body, is called hypochlorous acid (HClO) and it is a potent disinfectant. It is non-toxic to humans and is highly effective as an antimicrobial agent with rapid action. Hypochlorous acid is widely recognized as one of the most effective known biocides.

In detail, the system consists of an electrolysis cell containing two electrodes, a cathode and an anode, separated by a diaphragmatic membrane. In the cell is injected an aqueous solution consisting of filtered and softened water and, depending on the application, sodium chloride (NaCl, salt) or potassium chloride (KCl). With the use of electricity with predefined and controlled amperage and voltage values, the cell produces an electrically-activated liquid, Anolyte, with high disinfection power that can be used in a variety of applications.

This unipolar electrochemical activation created by potential gradients of millions of volts per cm2 between the anode and cathode terminals, results in the creation of solutions whose pH, Oxidation Reduction Potentials (ORP) and other physicochemical properties, lie outside of the range which can be achieved by conventional chemical means.



Electro-activated solutions produced by the system are respectively:

  • Acid Anolyte is a very strong oxidizing and disinfecting agent and can be used wherever there are no constraints on the pH value (in the absence of corrosion hazards). Acid Anolyte acts extremely quickly and effectively against all bacteria, viruses, spores, moulds, fungi and algae, even if diluted in water or nebulized.
  • Neutral Anolyte is used wherever a neutral pH (corrosion risk) is needed. Neutral Anolyte is extremely effective against a wide range of pathogens such as viruses, bacteria, spores, moulds and fungi.
  • Catolyte is a powerful reducing agent, it is alkaline and is an excellent detergent liquid that can also be used in flocculation and precipitation of heavy metals. It can also be used in applications where pH correction is required.
SolutionActive ElementpHORP/REDOX
Acid Anolyte Active Cl
500 / 700 ppm
2.5 / 5.0 1200 / 1000 mV
Neutral Anolyte Active Cl
500 / 700 ppm
6.0 / 8.0 950 / 850 mV
Catolyte Sodium hydroxide
1000 ppm
10.0 / 12.0 -800 / -900 mV


As presented in several scientific publications, multicellular organisms, including humans and hot blood mammals, to defend themselves against pathogens and foreign microorganisms are able to synthesize, through metabolism, complex mixtures of metastable oxidizing compounds.

These compounds possess a wide spectrum of action and are capable of damaging all major systemic groups of pathogenic microorganisms (bacteria, mycobacteria, viruses, moulds, spores, etc.) without damaging multicellular organisms and human tissues.

The oxidizing liquids and their chemical production mechanisms are similar to those generated in our ECA system and are precisely these common characteristics that give Anolyte a high biocompatibility with human tissues and multicellular organisms besides not being toxic to the environment.

Anolyte has the following advantages:

  • It has a high ORP (oxidation-reduction potential) value of between 850 and 1200 mV, obtained thanks to the numerous oxidizing compounds present in large quantities but each with low concentration; this peculiarity allows Anolyte to have much greater efficacy than chloramines, sodium hypochlorite and most other disinfectant and sterilizing agents.
  • It is a powerful biocidal product that kills pathogenic, viral and fungal microorganisms (Staphylococcus aureus, Legionella Pneumophila, Pseudomonas Aeruginosa, Bacillus Cereus, Escherichia coli, Listeria, Salmonella, Hepatitis B virus, virus Poliovirus, HIV, Adenovirus, Norovirus, pathogenic Tuberculosis, Dermatomycoses and other).
  • Thanks to the mixture of various metastable active ingredients of which it is composed, Anolyte eliminates the ability to adapt the microorganisms to its bactericidal effect, thus not allowing the developing resistance.
  • Has a low concentration of active oxygen and chlorine compounds, which guarantees absolute safety and non-toxicity to humans and animals, even after prolonged use of the Anolyte.
  • Can be applied in the liquid form, ice or aerosol (mist), in pure or diluted form.
  • Contrary to other disinfectants, it can be used as a multifunctional solution at all levels of disinfection, both as a detergent and as a sterilizer at the same time.
  • Degrading various organic compounds in harmless residues.
  • After its use, it degrades spontaneously without leading to the formation of toxic xenobiont (the synthesis products in biology).
  • Does not require any neutralization prior to disposal.

Anolyte and Catholyte also have the following characteristics:

  • Do not require special attention to handling.
  • Can be used in all stages of disinfection (Anolyte) and cleaning (Catolyte).
  • At recommended concentrations, do not bleach materials and surfaces.
  • Are hypoallergenic.
  • Have a quick action.
  • Their production only develops water, hydrogen and oxygen.
  • Generated by-products are not toxic, are environmentally friendly and do not leave chemical residues.
  • Can be generated in situ by eliminating the handling and storage of chemicals.
  • Can be safely disposed of in sewage systems.

Here you can find some ECA Water Applications


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Legionella Prevention


About Yasin Akgün

Yasin Akgün, of Turkish origin, was born in Munich on 22 May 1977. After completing his high school diploma he completed his studies of mechanical engineering at the TU Munich. Since 2006, he is the proud owner of the Munich watering place, which was in the inner courtyard of Fraunhoferstr. 13 from 1987 until 2018.
Since 2018 Aquacentrum has moved to Garching, a suburb of Munich.>More about Yasin Akgün in his biography
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