Iversen D B, Tolo K
Nor Tannlaegeforen Tid. 1975 Dec;85(11):446-8.
The filtrering effect of an electrostatic filtrattion equipment (Vortronic mod. 75) for air filtration was examined by sampling the air in a general dental practice by means of a Casella Slit Sampler for Airborne Bacteria (C. F. Casella & Co. Ltd., London). A reception, a sterilization, two treatment chairs and a resting cabinet were seperated by 180 cm high walls in a rectangular room of 33 m2 and with an air volume of approximately 80 m3. The staff including one dentist and one or two assistents worked from 8 a.m. till 4 p.m. with a 30 min. lunch break. A mean of 17 patients visited the practice every day. The electrostatic filter was placed in front of one of the treatment chairs and the slit sampler was, for one period, placed at a distance of 5 m from the filter. In the next period both filter and slit sampler were placed within 140 cm from the treatment chair. The air was sampled at noon and at 4 p.m. Micro-organisms from the air samples were cultured on blood agar by incubation at 37 degrees C for 48 hours. After incubation all colonies visible to the eye were counted. A total of 36 air samples were examined. Without filtration of the air the bacterial contamination amounted to 14 cultivable organisms per ft3 air at noon and 54 organisms per ft3 at 4 p.m. The filtration equipment proved to reduce the air contamination to 6 cultivable organisms per ft3.
采用用于空气中细菌检测的卡塞拉狭缝采样器（伦敦的C.F.卡塞拉有限公司）对一家普通牙科诊所的空气进行采样，以此来检测一款静电过滤设备（Vortronic型号75）的空气过滤效果。在一个33平方米、空气体积约为80立方米的长方形房间里，接待区、消毒区、两张治疗椅和一个休息柜被180厘米高的墙壁隔开。工作人员包括一名牙医和一两名助手，工作时间为上午8点至下午4点，有30分钟的午餐休息时间。平均每天有17名患者前来就诊。静电过滤器放置在其中一张治疗椅前方，狭缝采样器在一个时间段内放置在距离过滤器5米处。在下一个时间段，过滤器和狭缝采样器都放置在距离治疗椅140厘米以内。在中午和下午4点对空气进行采样。将空气样本中的微生物在血琼脂上于37摄氏度培养48小时。培养后，对肉眼可见的所有菌落进行计数。总共检测了36个空气样本。在未对空气进行过滤的情况下，中午每立方英尺空气中的细菌污染量为14个可培养微生物，下午4点为每立方英尺54个微生物。事实证明，过滤设备可将空气污染量降低至每立方英尺6个可培养微生物。
