Step 2, in which the conveyor was cleaned with water at room
temperature for 15 s was not included in the mathematical model.
Although this step theoretically could enhance the cleaning and
sanitizing treatments and so further reduce the residence probability
of viable bacteria for both microorganism groups, in contrast
the results of preliminary experiments revealed that the prevalence
of both microorganisms was not reduced when the surfaces
of conveyor were cleaned with water, except when the initial loads
were rather high (4–6 log CFU/ft2), when a 20–29 % reduction in
bacterial loads was observed