The effect of the ventilation rate on the air particle and air microbe concentration in operating rooms with conventional ventilation. 2. Measurement during surgical activity with respect to surgical personnel number and surgical activity phases
Kruppa, B.; Rüden, H.
Zentralblatt für Hygiene und Umweltmedizin 194(3): 247-261
1993
ISSN/ISBN: 0934-8859 PMID: 8338614 Document Number: 415004
For measurements with surgical activity, it was investigated if the air-exchange-rate has a significant influence on airborne particle and bacteria concentrations in two conventionally ventilated operating theatres. Next to that the influence of number of personnel in the operating theatre and the various operating phases were calculated (explanation of variance). Statistical differences were found for airborne particle concentrations and a few for airborne bacteria concentrations in supply and ambient air. From the hygienic point of view these differences must be considered to be irrelevant because of the little margin (less than one lg-step) between the values. The comparison of all air-exchange-rates as well as that between the two air-exchange-rates in the two operating theatres show that the number of personnel present in the operating theatre has the most influence on airborne particle concentrations variance. Concerning airborne bacteria concentrations explanation of variance by the treatment factors air-exchange-rate, personnel and operating phase is negligible. Summarizing the low (7.5 and 10/h) and high (15 and 20/h) air-exchange-rates did not increase the explanation of variance for airborne particle and bacteria concentrations although the differences were on a significant level.