Air systems treatment guidelines
Solutions
The importance of maintenance
It is necessary to provide adequate prevention me-
asures for regular monitoring and suitable main-
tenance of air conditioners. It is also essential to
provide for regular cleaning and sanitizing of equip-
ment and installation of filters, at the beginning and
at the end of the air duct, in order to preserve the
internal components of the system.
Cleaning
As for cleaning operations, no reference is made to
specific products: water and generic cleaners are
sufficient for both ordinary sanitization and extra-
ordinary (i.e. the one to be operated as a result of
positive case feedback to contamination).
Disinfection
As regards disinfection operations, the ISS shall
always specify that products which have a disin-
fectant, bactericidal, fungicidal, virucidal or any
other action aimed at destroying, eliminate or ren-
der harmless microorganisms, relapse into distinct
regulatory processes: that of Biocide under tran-
sitional Legislation (PMC) and that of Biocides.
In both cases, before they are placed on the mar-
ket, the products must be approved at national or
European level.
In the ISS report no. 19 is given an analysis of whi-
ch products are suitable:
Biocide under transitional Legislation (PMC)
For Biocide under transitional Legislation (PMC), as re-
quired by article 1 of the P.D.R. 392 of 6 October 1998,
the following types of products are understood:
• disinfectants and substances placed on the market as
germicidal or bactericidal
• insecticides for domestic and civil use
• insect-repellent
• rodenticides for domestic and civil use
The use of PMC products has only national value. The
same document explains which are the main active prin-
cipals most used in the PMC authorized in Italy, speci-
fying the relevant scope.
PT1: “products applied to or in contact with the skin
or scalp for the main purpose of disinfecting the
skin or scalp”
PT2: “disinfectant products not intended for direct
application to humans or animals”
Therefore: any product that carries on the label the
wording PMC, with its registration code according
to the P.D.R. 392 of 6 October 1998, containing the-
se active ingredients (and the others indicated in
the report) is suitable for surface disinfection.
Prevention in systems
In water systems, it is always good practice to pro-
vide, along with proper and careful maintenance,
an appropriate disinfection treatment in order to
guarantee the achievement of qualitative parame-
ters adapted to current requirements, in complian-
ce with the provisions of law, in particular Legisla-
tive Decree n. 31 of February 2, 2001. Given their
size, bacteria can penetrate very easily in our hy-
draulic systems, often aided by tiny insects very
mobile and able of getting in. Once into the system,
they tend to move on all surfaces of vessels and
pipelines, regardless of the materials of which are
made of, although some studies show that Biofilm
(ecological niche that represents for opportunistic
pathogenic bacteria an excellent shelter and sour-
ce of nourishment) grows faster than inside plastic
pipes compared to metal tubes, since microorgani-
sms consume the nutrients present in the organic
content of the material that makes up the pipe itself.
56