Effects of contact time and concentration on bactericidal efficacy of 3 disinfectants on hard nonporous surfaces

摘要

Highlights ? All 3 tested disinfectants were significantly less bactericidal at contact times or concentrations significantly lower than the label values. ? The bactericidal efficacy of the sodium hypochlorite disinfectant was most tolerant to the decreases of contact times and concentrations, followed closely by accelerated hydrogen peroxide disinfectant, and quaternary ammonium compounds disinfectant was most affected. ? In health care facilities, deviations from disinfectant direction of use, such as shorter wet contact time, could result in suboptimal disinfection. This study investigated the influence of contact time and concentration on bactericidal efficacy of 3 types of disinfectants (accelerated hydrogen peroxide [AHP], quaternary ammonium compounds [Quats], and sodium hypochlorite) on stainless steel surfaces using Environmental Protection Agency procedure MB-25-02. We found that bactericidal efficacy was not reduced at contact times or concentrations immediate lower than label use values, but all 3 disinfectants were significantly less bactericidal at significantly lower than label use contact times and concentrations. Overall, the bactericidal efficacy of the sodium hypochlorite disinfectant was most tolerant to the decreases of contact times and concentrations, followed closely by AHP disinfectant, and Quat disinfectant was most affected by contact time and concentration. ]]>