Source strengths obtained with three clean air suits fulfilling the requirements for high performance in EN 13795-2:2019: An experimental study

Introduction: Clothing made from tight material worn by operating room staff adds to the effect achieved by ventilation in the effort to keep a low level of bacteria in the operating room air. The material used for clean air suits should be tested according to the standard EN 13795-2. Aim: The aim of the study was to investigate whether there was a difference in protective capacity between three clean air suits made from materials fulfilling the requirements of EN 13795-2:2019 and designed as described in Annex E of the standard. Materials and methods: Eight people (five men and three women) performed standardized movements in a dispersal chamber with a fixed supply air flow. Each person performed two test cycles with each clean air suit. Counts of colony-forming units (CFU) in the air were measured during testing and source strength was calculated for each test cycle. Results: The mean values of source strength for the three clean air suits were 1.4 CFU/s, 0.8 CFU/s and 0.7 CFU/s. The difference between the most and the least protective garment was statistically significant (p < 0.05). Conclusions: Clean air suits made from material fulfilling the requirements for ‘high performance’ in the standard EN 13795-2:2019 might show a significant difference in protective capacity when comparing source strength. Tests for measuring of source strength in a dispersal chamber can be performed as suggested in Annex E of the standard, i.e. ‘The test person is male, 20–50 years old, with no visible skin disorder’