The class 100 operating room’s environment must be controlled. Especially the temperature and humidity. Therefore, the operating room temperature in the design is set at t=22-25°C; the relative humidity is 35-60%. And the corresponding air conditioner and humidifier are configured according to different sizes of rooms.
According to the principle of the three-zone and two-channel. The pressure of the surgical department is arranged from large to small as special clean operating room, general clean operating room, clean corridor, vertical passage and dirt gallery.
Introduction of Pressure Difference in Class 100 Operating Room
The cleanliness level of the clean corridor is lower or equal to that of the general clean operating room. So there is a pressure difference between the two. The dirt gallery is the lowest cleanliness level in the entire surgical department. So the pressure difference between the operating room and the dirt gallery is greater than 5Pa. This can ensure the reasonable flow of airflow between different areas and prevent the invasion of external pollution.
For the operating room. In order to maintain the cleanliness of the room and avoid contamination by the adjacent room. It is necessary to maintain a high air pressure relative to the adjacent room. That is, maintain a positive static pressure difference with the adjacent room. The existence of the static pressure difference prevents the outdoor air from entering the clean room from the gap when the door and the window are closed. In addition, when the door is opened, there should be enough airflow to flow outward to minimize the polluted air that the person brings in instantaneously. To prevent gap penetration, generally two adjacent rooms should maintain a pressure difference of 5Pa. While the outdoor should maintain a pressure difference of 15Pa.
Design of Pressure Difference in Class 100 Operating Room
For the class 100 operating room. It must be satisfied that when the door is momentarily opened. The gas brought in by the person is not 0.6 meters away from the entry port. Moreover, the working area of the general clean room is 0.8-1.5 meters from the ground. The flow rate of the vertical laminar flow operating room is 0.25-0.3 m/s, and the door height is about 2.0 m. Vo/V=(2.0-0.8)/0.6, V=0.15 m/s, that is, when the external speed is not more than 0.15 m/s does not affect the indoor laminar flow, according to the “Air Clean Technology Principles”, the airflow velocity is 0.2m/s when entering the door, so the airflow velocity from the clean room is: V1=0.2-V= 0.2-0.15 = 0.05 m/s.
Assuming that the operating room door is 1.5 meters wide, the area of the door is: A = 2 * 1.5 = 3.0 square meters, so the air volume Q = A * V = 3.0 * 0.05 = 0.15 cubic meters / second, that is, 540 cubic meters / hour. Therefore, when the positive pressure air volume in the operating room is more than 540 cubic meters / hour, the laminar flow requirement can be satisfied.