Any cleaning regime requires the selection of the correct detergent and disinfectant strength, with routine checks carried out to ensure that this desired strength has been met.
Most acid or caustic, cleaning in place (CIP), detergents can be monitored in-line by conductivity. The conductivity probe and controller must be calibrated and temperature compensated to ensure accuracy; as a general rule each 1°C rise in temperature will increase conductivity by approximately 2%.
With peracetic acid and chlorinated based products redox measurement is generally used because conductivity tends to be unreliable and inaccurate.
The strength of detergents or disinfectants should be checked regularly through chemical titration. This can be done either in a QC Laboratory using traditional glass burettes or by a dropper bottle method, with the chemistry identical in both.
A common misconception is that a burette is more accurate than a dropper, but this is largely untrue with a dropper often delivering a more precise measurement.
Colour change test strips provide a quick indication on the approximate concentration of certain active components in a detergent or disinfectant, whilst pH paper will deliver a quick indication of any residual acidity or alkalinity following on from a detergent clean.
Test strips looking for PAA and QAC can give a good indication as to the strength of the disinfectant.
Disinfectant and acid test methods will traditionally report strength as % v/v product. Caustics strength can either be reported as % v/v product, or % wt/v NaOH (Sodium Hydroxide) commonly referred to as Causticity.
v/v - volume / volume
wt/v - weight / volume
Simple test kits are available for most detergents and disinfectants that are used and also for testing water hardness. Please contact our sales office for further information.