The aim of this study was to assess the impact of ventilation and filtration conditions on particle concentrations in an orthopedic operating room. Total particle, viable particle, and CO2 concentration were measured under three different situations, namely before air filter replacement, after air filter replacement, and in an operating room with a new air conditioning system. Before air filter replacement, the mean values of airflow, total particle concentration, and viable particle concentration were 706 m3/h, 15.0 × 106 ± 4.0 × 106 particles/m3, and 57 CFU/m3, respectively. After replacement, the airflow increased to 1954 m3/h, and total and viable particle concentrations decreased to 0.4 × 106 ± 0.2 × 106 particles/m3 and 24 CFU/m3, respectively. In the room with a new air conditioning system, the airflow was 2051 m3/h, and total and viable particle concentrations were 0.3 × 106. ± 0.1 × 106 particles/m3 and 15 CFU/m3, respectively. The CO2 levels were 663 ppm (before), 659 ppm (after), and 574 ppm (new room). The results showed that inappropriate or no maintenance of filters in an air conditioning system had significant negative effects on indoor air quality in operating rooms. Air conditioning systems operating with saturated filters can be affected by pressure drop, which can lead to a reduction in airflow, thereby resulting in an increase in the average total particle and viable particle concentrations and the risk of infection in operating rooms. However, the results showed that the CO2 concentration was not affected by the filter replacement. Improper maintenance of the air filters poses negative effects in operating rooms. Particles remain inside the room with less air exchange caused by saturated filters. Change in filters produces a greater effect on air quality in operating rooms. CO2 concentration generated by the people may not be affected by the filter replacement. Improper maintenance of the air filters poses negative effects in operating rooms. Particles remain inside the room with less air exchange caused by saturated filters. Change in filters produces a greater effect on air quality in operating rooms. CO2 concentration generated by the people may not be affected by the filter replacement.

中文翻译：

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过滤条件对手术室空气质量的影响

本研究的目的是评估通风和过滤条件对骨科手术室中颗粒浓度的影响。在空气过滤器更换前、空气过滤器更换后和装有新空调系统的手术室中，测量了三种不同情况下的总颗粒、活颗粒和 CO2 浓度。更换空气过滤器前，气流、总颗粒浓度和活颗粒浓度的平均值分别为 706 m3/h、15.0 × 106 ± 4.0 × 106 个颗粒/m3 和 57 CFU/m3。更换后，气流增加到 1954 m3/h，总颗粒浓度和活颗粒浓度分别下降到 0.4 × 106 ± 0.2 × 106 颗粒/m3 和 24 CFU/m3。在装有新空调系统的房间中，气流为 2051 m3/h，总和活粒子浓度分别为 0.3 × 106。± 0.1 × 106 粒子/m3 和 15 CFU/m3。CO2 水平为 663 ppm（之前）、659 ppm（之后）和 574 ppm（新房间）。结果表明，空调系统中过滤器维护不当或不维护对手术室的室内空气质量有显着的负面影响。使用饱和过滤器运行的空调系统会受到压降的影响，这会导致气流减少，从而导致平均总颗粒和活颗粒浓度增加，并增加手术室感染的风险。然而，结果表明 CO2 浓度不受更换过滤器的影响。空气过滤器维护不当会对手术室产生负面影响。由于过滤器饱和，空气交换较少，颗粒留在房间内。更换过滤器会对手术室的空气质量产生更大的影响。人产生的 CO2 浓度可能不受更换过滤器的影响。空气过滤器维护不当会对手术室产生负面影响。由于过滤器饱和，空气交换较少，颗粒留在房间内。更换过滤器会对手术室的空气质量产生更大的影响。人产生的 CO2 浓度可能不受更换过滤器的影响。空气过滤器维护不当会对手术室产生负面影响。由于过滤器饱和，空气交换较少，颗粒留在房间内。更换过滤器会对手术室的空气质量产生更大的影响。人产生的 CO2 浓度可能不受更换过滤器的影响。空气过滤器维护不当会对手术室产生负面影响。由于过滤器饱和，空气交换较少，颗粒留在房间内。更换过滤器会对手术室的空气质量产生更大的影响。人产生的 CO2 浓度可能不受更换过滤器的影响。