Abstract: Apparatus is provided for detection of viable and potentially hazardous biological particles in a population which may be dispersed in fluid flow. The particles are characterized as biological and viable by contacting particles with laser light from a laser diode and then looking for the emission of fluorescence which is typically emitted from bacteria or bacterial spore. Biomolecules which are representative of viability are now known to be excited in range of 320 nm and longer. The resulting apparatus is economical, compact and has low-power requirements enabling portable operation. Preferably, the laser diode is combined with an aerodynamic particle sizer to separate particles for sequential contacts, or with additional timing lasers for establishing particle size.

Abstract: Apparatus is provided for detection of viable and potentially hazardous biological particles in a population which may be dispersed in fluid flow. The particles are characterized as biological and viable by contacting particles with laser light from a laser diode and then looking for the emission of fluorescence which is typically emitted from bacteria or bacterial spore. Biomolecules which are representative of viability are now known to be excited in range of 320 nm and longer. The resulting apparatus is economical, compact and has low-power requirements enabling portable operation. Preferably, the laser diode is combined with an aerodynamic particle sizer to separate particles for sequential contacts, or with additional timing lasers for establishing particle size.

Abstract: A process and apparatus are provided for detection of viable and potentially hazardous biological particles which may be dispersed in a particulate-containing airstream. The process comprises directing each of the contained particles along a linear path through air, in a sequential manner, and sampling them for determination of their size, whether they are biological and viable, and whether they are present in concentrations greater than background levels. The particle size identifies the particles as respirable or not and the particles are characterized as biological and viable by subjecting each particle in turn, to 340 nm, ultraviolet laser light and looking for the emission of fluorescence which is typically emitted from bacteria or bacterial spore. Fluorescence detected in the 400-540 nm range signals the presence of nicotinamide adenine dinucleotide hydrogen, which is indicative of biological activity or viability.

Abstract: A process and apparatus are provided for detection of viable and potentially hazardous biological particles which may be dispersed in a particulate-containing airstream. The process comprises directing each of the contained particles along a linear path through air, in a sequential manner, and sampling them for determination of their size, whether they are biological and viable, and whether they are present in concentrations greater than background levels. The particle size identifies the particles as respirable or not and the particles are characterized as biological and viable by subjecting each particle in turn, to 340 nm, ultraviolet laser light and looking for the emission of fluorescence which is typically emitted from bacteria or bacterial spore. Fluorescence detected in the 400-540 nm range signals the presence of nicotinamide adenine dinucleotide hydrogen, which is indicative of biological activity or viability.