Bacterial flora of hospital carpets

Abstract

An experiment was set up in Christchurch Hospital to attempt to identify and quantify the bacterial flora of carpet and sheet vinyl floor coverings in a ward and laboratory area, and the bacterial flora in the air of the same area noting any bacteria/fibre relationships, as well as determining the effect of ambient temperature, humidity and people on the bacterial counts. The test areas were a blind ward corridor and a first floor laboratory corridor. Both areas had rooms with windows opening to the outside leading off each side of the corridor. Analytical samples were collected from predetermined sites using settle plates, a Casella slit sampler and a vacuum sampler. Studies were carried out before, during and after a 12 ft length of carpet was laid over the complete width of each corridor. Analysis of the results showed: (1) The difference in numbers of bacteria on the settle plates, number and types of bacteria on the floor and in the air, from the vinyl and carpeted floor areas was generally not significant. (2) There was no evidence that carpet harbours any more pathogenic bacteria than a sheet vinyl floor covering. (3) There was no statistical relationship between the fibre count and the bacterial count of the settle plates from the carpeted floor areas. (4) The bacterial counts were significantly lower 18 ft from the entrance of each corridor no matter which floor covering was in situ , but these counts were significantly lower when the corridor entrance was carpeted. (5) There was no statistical correlation between the bacteria counted and the recorded humidity or temperature.