LEGIONELLA in systems, how to prevent it and fight it

Legionella is a microorganism commonly found in na-

ture, where it is mainly associated with the presence of

water, whether it be rivers, lakes, reservoirs, thermal

springs or human use when it flows out of our taps. To-

day, infections caused by Legionella are a serious and

worrying problem due to the ever-increasing presence

of bacteria in hot water at homes, hotels, campsites,

swimming pools, hospitals, nursing homes, and in any

situation where the water temperature is at least 25 °C.

One thing that clearly does not help is the return circuit

of central heating systems and the large amounts of

hot water stored, due in some cases to solar power

systems, thus putting into question the safety of sha-

red systems in apartment blocks or other similar resi-

dential buildings, where the Legionella risk is growing

and growing. But that is not all... Particularly high and

dangerous concentrations can also be found in air con-

ditioning systems made up of cooling towers, evapo-

rative condensers or air humidifiers. We are often fa-

ced with this problem in existing systems where there

are already many issues such as corrosion, limescale,

dead circuit branches in which there is no continuous

water circulation, and accumulations not regularly mo-

nitored, all of which are aspects that favour the growth

of Legionella itself.

A “dangerous” bacterium

The bacteria actually enter our body through the

airways by the inhalation or aspiration of aerosols.

The smaller the drops of water, the more the germ can

easily reach the lower respiratory tract, especially the

lungs. There are various sources of aerosols: turning

on tap or a shower fed by a contaminated water sy-

stem, whirlpool bathtubs and swimming pools; Turkish

baths and saunas; ornamental fountains especially if

located indoors; garden irrigation systems, waste wa-

ter systems, cooling towers and evaporative conden-

sers, and air conditioning systems in general. The lat-

ter, in places where they have been installed, create a

real Legionella risk if they do not receive adequate and

regular maintenance.

The importance of maintenance

It is necessary to provide adequate prevention mea-

sures for regular monitoring and suitable maintenance

of air conditioners.It is also essential to ensure regular

cleaning and sanitising of equipment and the instal-

lation of filters, at the beginning and at the end of the

air duct, in order to preserve the internal components

of the system. For this, Facot recommends the use of

the CLIMANET and CLIMASAN sanitisers, ideal for

killing and eliminating Legionella bacteria, also in ac-

cordance with the provisions of Law 155 on HACCP.

CLIMANET Spray with a foam-detergent action can be

used for the treatment of finned radiators of air condi-

tioners and fan-coils, finned packs, internal and exter-

nal parts; CLIMASAN Spray, on the other hand, can

be used as a sanitising-deodorising product (pleasant

scented), with an antibacterial-germicidal action, spe-

cially designed for air conditioner filters, car filters, etc.

Alternatively, we can use CLIMANET in a concentrated

liquid version, with a detergent-degreasing action, to

be diluted with water to 1 - 5 % and sprayed directly

onto the surface to be sanitised using special foaming

nozzles; or CLIMANET FILTRI, specifically designed

to clean and sanitise industrial filters of hot air genera-

tors, air conditioning systems, but also extractor hoods

for bars, community centres, restaurants, as well as for

the removal of fatty substances in general from PVC

tarpaulins, covers, vehicles, etc.

Prevention in water systems

In water systems, it is always good practice, besides

proper and careful maintenance, to perform adequate

disinfection treatments in order to ensure you achieve

the quality parameters in line with current needs, in

compliance with legal requirements, in particular Le-

gislative Decree n° 31 of 2 February 2001. Given their

size, bacteria can actually penetrate very easilyin our

hydraulic systems, often assisted by tiny insects that

are very mobile and able to enter. Once in the system,

they tend to settle on all surfaces of tanks and pipes,

regardless of the materials with which they are made,

although some studies show that the Biofilm (ecologi-

cal niche that represents for opportunistic pathogenic

bacteria, an excellent source shelter and nourishment)

develops faster inside plastic pipes than metal ones,

since microorganisms use the nutrients present in the

organic content of the material that constitutes the pipe

itself.

Enterobacteria

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