A clean is deemed effective when the desired levels of cleanliness, chemical, physical and microbiological have been achieved.
Testing whether this is the case can be done through a number of techniques; the choice of test depending on the risk that is being controlled (microbiological, physical, chemical).
It is possible to measure the bacterial contamination on a surface by traditional swabbing and evaluation techniques, however this process does take time and cannot be used when quick feedback is required during the cleaning process.
It may also be necessary to carry out allergen and species testing, with laboratory techniques continually being developed that provide good sensitivity and repeatability.
This includes Elisa test methods which detect quantitatively the presence of specific proteins that are associated with allergic reaction, otherwise known as allergens. It is also possible to use DNA testing to look for allergens and animal species.
Measurement of the residues of food can also be carried out, and can give quick results during the cleaning process to establish whether a re-clean is required.
For example ATP testing uses the presence of Adenosine Triphosphate on reaction to create pulses of light that can be read using an instrument. Also protein or glucose testing and rapid allergen testing can identify any residues on a surface determining whether a re-clean needs to take place.
Cleaning validation involves showing that the defined cleaning sequence and associated parameters achieve the desired cleaning result for a given set of soiling conditions. Once a cleaning dequence has been validated as being effective repeating the sequence should always achieve the required results.
Cleaning verification is on-going confirmation through testing or evidence that the cleaning process is meeting the specified standards.