KEOFITT W9 USER MANUAL V.4 PAGE 10
2. CLEANING – DISINFECTION – STERILISATION
This chapter gives introduction to the concepts of cleaning, disinfecting and sterilising process
equipment in general, but with focus on sampling valves.
2.1 Clean-In-Place (CIP)
Thorough cleaning of the valve is a prerequisite for proper disinfection or sterilisation. Cleaning of the
valve is the removal of any visible residual product, it be organic or inorganic. It may be done using either
steam (continuous steam will eventually lead to sterility; SIP = Sterilise-In-Place) or a suitable liquid
detergent.
Cleaning is the removal of adhering soil from the environment and from the previous sample (to
the extent it has not been removed by the recommended post-sample cleaning). Cleaning is usually
performed by ushing with water followed by a thorough washing with an appropriate detergent and
nished o with a thorough rinsing with water.
Depending on the actual process media the proper detergent must be determined in cooperation with
your usual supplier of detergents. The company Novadan ApS, Kolding, Denmark - www.novadan.dk, has
supplied the generic table below for your convenience.
What to clean for Generic cleaning agents Comments
Fat Alkali and Tensides Heat will facilitate the cleaning process
as the fat melts
Protein Alkali, Acids, Tensides and Chlorine Coagulation and burning when heated,
which makes the product hard to
remove.
Sugar, Salt Water is usually suicient as the
product is water soluble
Sugar caramelises when heated,
turning into a hard sticky substance,
which is diicult to remove
Minerals Acids, Complexing agent Oen seen as lime scale
Biolm Alkali and Chlorine, Peracetic acid,
possibly Enzymes
Biolm is an accumulated mass of
microorganisms that is tightly adhered
to a surface and cannot be easily
removed.
Starch Alkali and Chlorine
2.2 Disinfection
Although CIP removes all visible residues of the process media the valve surfaces will still be
contaminated on a microscopic level. Depending on your actual process media it will be necessary to
carry out a disinfection operation in order to a) reduce the microbial load to an acceptable level (also
referred to as Sanitization) or b) destroy critical microorganisms, but not necessarily all microbial forms
(e.g. bacterial spores).
The disinfection process may be carried out in one of two ways and to dierent levels of disinfection
depending on a) the initial microbial load distribution, b) the required hygienic level and c) the type,
exposure time and concentration of the chemicals used (if using a chemical disinfectant):
• By steaming (in a continued process aer steam cleaning)
• By applying one or more suitable liquid chemical disinfectants
There are a number of chemical disinfectants. It is important to choose the right one, the right
concentration and contact time and the right method for your current application. Your usual supplier of
chemical disinfectants can support you in choosing the right disinfectant for your process media and the
specic group of microorganisms you are aiming at.