Patent ID: 7224825
Filing Date: 2007-05-29
Classification: G01N

Abstract:
1. A method for detecting airborne particular matter comprising a plurality of particles, comprising: measuring the backscatter induced by each of the particles under a light source to determine a backscatter value for each particle; measuring the autofluorescence intensity of each of the particles around at least one characteristic wavelength to obtain at least one autofluorescence intensity value for each particle; processing the measured autofluorescence intensities and the backscatter values from the plurality of particles to categorize the plurality of particles into at least two event categories, such that each category has an associated particle count; determining a weighting factor from the associated particle counts of the at least two event categories; applying the determined weighting factor to a total particle count to produce an adjusted particle count; comparing the adjusted particle count to a threshold value to determine if a potential biohazard exists.