Lack of natural ventilation: ① natural ventilation is variable, depending on the relative indoor outdoor weather conditions. Two driving forces generated by wind speed (wind and temperature difference) diverse. Natural ventilation is relatively difficult to control the operating room decontamination, air may be high in some parts, while other parts will no airflow. Under certain adverse weather conditions, may lead to a lower air exchange rate. ② lack of sustained negative pressure conditions favorable operating room purification price, natural ventilation will be difficult to control the wind, sometimes the risk corridor with adjacent room mutual contamination. ③ natural ventilation can not use dust filter; due to climatic reasons, security, cultural background as a result we are not used to open doors and windows closed, in such an environment will be very low ventilation rates. ④ natural ventilation is available only when the onset of the forces of nature; when high ventilation time, higher demands on the wind. ⑤ natural ventilation systems often stop working, normal operation is terminated due to a variety of reasons, including its doors not open, poor equipment damage, utility failures, design, improper maintenance, neglect of management. ⑥ although simple natural ventilation system maintenance costs low purify the operating room, but if not installed properly, lack of maintenance funds, its effect will be greatly reduced operating room ventilation purification materials, the risk of airborne pathogens lead to an increase. These problems can be overcome by good design or use of hybrid ventilation. Other possible defects, such as noise, air pollution, contaminated insects, security also needs to be considered. Because of these problems, natural ventilation system not only can not serve as an effective infection control facilities, but these facilities caused by the spread of infectious diseases. Mechanical ventilation is through the installation of ventilation equipment, the use of power blowers, fans, etc. produced by the operation, the air flow and carried ventilation. Mechanical ventilation systems including ventilation equipment, ventilation pipes, exhaust hood (or outlet) and purification equipment. WHO "natural ventilation for infection control medical institutions (2009)," The advantages and disadvantages of mechanical ventilation and natural ventilation were compared. Operating room purification classification, Suihua purify the operating room, the benefits provided by the German operating room decontamination Ltd. Shandong Yick Tak. Operating room purification classification, Suihua purify the operating room, operating room Ecota Shandong Ecota decontamination Ltd. (www.shandongyide.cn) launched this new upgrade, the above picture is for reference only, please call or pictures on this page contact telephone number, to obtain the latest information, contact: Housing Manager.