Air sampling procedures to evaluate microbial contamination: a comparison between active and passive methods in...

Area of Science:

• Environmental microbiology
• Healthcare-associated infection control
• Air quality monitoring

Background:

• Airborne microorganisms pose risks in controlled environments like operating theatres.
• Regular microbial monitoring is crucial for assessing air quality and identifying potential contamination issues.

Purpose of the Study:

• To evaluate microbial contamination levels in operating theatres using active and passive sampling.
• To determine the correlation between active and passive air sampling methods.

Main Methods:

• Study conducted in 32 turbulent airflow operating theatres.
• Active sampling utilized the Surface Air System; passive sampling used settle plates (ISO 14698).
• Total Viable Count (TVC) assessed at rest and during surgical operations.

Main Results:

• Mean TVC at rest: 12.4 CFU/m³ (active) and 722.5 CFU/m²/h (passive).
• Mean operational TVC: 93.8 CFU/m³ (active) and 10496.5 CFU/m²/h (passive).
• Statistical analysis confirmed a comparable correlation between both methods and air quality.

Conclusions:

• Both active and passive sampling methods are suitable for general air contamination monitoring.
• Methods can be employed for routine surveillance in healthcare settings.
• Method selection depends on the need for specific information.