The assessment of the bactericidal activity of surface disinfectants. IV. The AOAC use-dilution method and the Kelsey-Sykes test.

The AOAC use-dilution method was applied in order to assess the bactericidal activity of 29 commercial preparations for surface disinfection and the Kelsey-Sykes test under clean conditions for 38 preparations. The results of both tests are compared with those of the in vitro test (with the disinfectant diluted in distilled water, in water of standardized hardness, and in a 0.2% albumin solution), those of the European suspension test under clean and under dirty conditions, and those of four practical tests (the AFNOR test, the DGHM test, the QCT and the QSDT). Both the AOAC use-dilution method and the Kelsey-Sykes test under clean conditions are more severe than the suspension tests and, in the case of Pseudomonas aeruginosa, even than most practical tests. The results of both tests correlate well to one another, and to the results of in vitro test, but less to those of the European suspension test. For the practical tests the correlation depends on the testing technique and on the test organism.