Inefficiency of upward displacement operating theatre ventilation

Zoned exponential, vertical and horizontal ultra-clean laminar airflows: No differences in bacteriological efficiency

“…For reference, 20-100 cfu/m3 were recorded in a conventionally ventilated operating room during identical sham surgery (Friberg et al 1996b). (51) 64 (40) 32 (37) Instruments 26 (38) 7 (13) 32 (45) Inside the LAF, no significant differences were recorded between the air flows.…”

Zoned vertical ultraclean operating room ventilation: A novel concept making long side walls unnecessary

“…For reference. 8500 partides z 10.0 pm were recorded in a conventionally-ventilated operating room during Identical sham surgery (Friberg et al 1996). the "patient" (4 plates), in the "wound" area (2 plates) and on the "instrument" table (4 plates) were studied only during sham surgery (30 min.…”

“…In general, it has been found to generate bacterial dispersal rates equivalent to those reported for real surgery performed during similar conditions (Whyte et al 1983b, Hambraeus 1988, Ah1 et al 1995. There are several advantages with an experimental model (Friberg et al 1996). One is that the strict standardization of individuals, speech, and physical activity will give rather constant bacterial dispersal rates from the team, resulting in small standard deviations that will reduce the number of experiments required for a study.…”

“…The model has earlier been described in detail and only information relevant to this study is given (Friberg et al 1996).…”

Experimental Investigation of Exhaled Aerosol Transport Under Two Ventilation Systems

“…The authors concluded that this system offers the best particle removal efficiency for their steady-state measurements. Friberg et al (1996) compared the performance of displacement ventilation with that of a conventional positive pressure system during rigidly standardized sham operations. They concluded that although the displacement ventilation system examined was more efficient in eliminating particles of less than 10 µm, the major shortcoming of the system was its failure to eliminate a sufficient quantity of larger bacteria-carrying airborne particles.…”