Practical Safety Ventilation in Ultraclean Air Operating Rooms
Licentiate thesis, 2018
When planning new ultraclean air operating rooms, often the first question is which is the preferred room air distribution system and
what system is the best to meet the requirements of microbiological air cleanliness. Today, in Sweden, the requirement is a target level of
5 CFU/m3during the design phase, in order to ensure that the level of ≤10 CFU/m3during infection prone surgery is maintained.
This study is based mainly on the analysis of published scientific reports and other documentation. The focus is to compare the main
principles for room air distribution systems, mixing and displacement principle and to see whether the requirements of microbiological air
cleanliness can be fulfilled during ongoing surgery. Three different distribution systems available in Sweden have been compared.
The room air distribution systems studied are:
· Mixing airflow/partly displacement
· Unidirectional airflow (UDF)
· “Temperature controlled airflow (TAF)” - A specific Swedish room air distribution system.
The result of the comparison shows that in operating rooms for infection prone surgery all three studied room air distribution systems
could achieve the target level of 5 CFU/m3 when the air volume flows are above 2 m3/s provided that the total microbiological source
strength does not exceed 10 CFU/s.
The total microbiological source strength depends upon the number of people in the operating room, their chosen surgical clothing system,
and their activity level.
Keywords: Ultraclean operating room, room air distribution system, airborne bacteria-carrying particles, microbial source strength, surgical clothing system
airborne bacteria-carrying particles
microbial source strength
surgical clothing system
room air distribution system
Keywords: Ultraclean operating room
Chalmers, Architecture and Civil Engineering, Building Services Engineering
Areas of Advance
Building Futures (2010-2018)
Innovation and entrepreneurship
Other Civil Engineering
Learning and teaching
Chalmers University of Technology
SB-H3, bottom floor, ACE, Building SB1 (Sven Hultins gata 6)
Opponent: Johan Nordenadler, PhD, Project manager at Karolinska University Hospital