APPLICATION OF THE IMD IN MEASUREMENT OF AIRBORNE MICROBIAL PARTICLES

Traditional method for measuring airborne microbes is based on two procedures called sampling andincubation. Sampling normally involves drawing a sampler from an air stream or room by means ofinstruments based on 3 types collecting-method, which named impaction, liquid impingement andfiltration. Incubation of agar plates typically requires several days. Though the traditional methods canidentify the species of microorganisms, they can't obtain any information about suspended viableparticles in real time.Recently, outbreaks of microbial infections and measures of bioterrorism have been the subject ofsocial attention. The technology for real time detection of the presence of suspended viable particleswas developed. In order to verify the performance of a new type measurement IMD (InstantaneousMicrobial Detection, Bio Vigilant, Inc.), which is used to measure the concentrations of suspendedparticles with different size distribution based on optical technology and can simultaneously determinewhether each particle is inert or biologic in real time, measurements on airborne microbes in sixhospital waiting rooms located in Tokyo area were conducted by using parallel an IMD and MGsampler (culture-based, slit type, Mattson-Garvin Inc.).Significant correlations between suspended bacterial concentration and biological particleconcentration were obtained. The measurement results pointed out that the IMD can measure thefluctuation patterns of suspended biological particles in field environments in real time.