Patent ID: 7385204

Claim:
A fluid treatment device comprising: a. a housing for receiving a flow of fluid, said housing comprising a fluid inlet and a fluid outlet; and b. at least one assembly of UV sources between said fluid inlet and said fluid outlet, said assembly comprising at least two UV sources horizontally disposed in a substantially vertical plane transverse to the flow of fluid, at least one of said at least two UV sources being disposed in said plane below such other UV sources as a bottommost UV source, and at least one of said at least two UV sources being disposed in said plane above such other UV sources as an uppermost UV source, said bottommost UV source operating at the same or a higher power level than that of all such other UV sources in said assembly such that said fluid flowing below said bottommost UV source receives a UV irradiance that is at least substantially equal to a UV irradiance received by said fluid flowing above said uppermost UV source.