December 11, 2001
An apparatus for killing microorganisms in a primary flow of a fluid medium using germicidal beams to kill microorganisms in a portion of the primary flow of the fluid medium has a housing having an inlet end 1 and an outlet end 4 . The housing 20 has reflective inner surfaces 2 R, 3 R, 5 R and 6 R along the path 100 of the germicidal beams, a source 30 of germicidal beams located in the housing 20 and at least one baffle 40 located near the source 30 of the germicidal beams. The baffle 40 projects from an inner surface 6 of the housing 20 and is configured to converge the primary flow of air into the germicidal beams path in close proximity to the germicidal beams source 30 . The at least one baffle 40 has an upstream portion 41 lying substantially out of the beam path 100 and a downstream portion 42 lying in the beam path 100.