Biotrak real-time viable particle counter 9510-bd product details The BIOTRAK® Real-Time Viable Particle Counter offers best-in-class features and versatility in the exciting new field of real time airborne viable particle detection. The BIOTRAK particle counter detects total and viable particle counts in real time and incorporates TSI field proven, patented Laser Induced Fluorescence (LIF) technology to determine particle viability.TSI's BIOTRAK Real-Time Viable Particle Counter combines viable particle detection, total particulate detection, and integrated particle collection functionality into a single portable instrument.