Where the parameters are appropriate for the removal of air and the penetration of steam, then all nine steam steriliser
indicators should show no colour change, in other words, they should indicate complete killing of the spores or deactivation
of the spore enzymes as appropriate. If there is a colour change, which signifies a failed test result, the holding time for the
steam steriliser should be increased in increments of one or two minutes, and the entire validation procedure repeated, in
order to establish the minimum time required. The results of the validation process must be recorded.