in accordance with fig1 and 2 flat member 17 constitutes a lower collector for grease particles and impurities which are thereafter drained away from the hood through drain 27 turning now to upwardly inclined flat member 19 first it will be seen to be associated with flat member or lower collector 17 at joint 15 in other words flat member 19 is a continuation of flat member 17 but which abruptly changes direction at 15 by being suddenly upwardly inclined to constitute an inlet deflector in the illustrated embodiment deflector 19 forms an angle u03b1 of approximately 135 u00b0 with lower collector 17 it being understood that this angle may vary to some extent depending on design and purposes intended to be achieved the chosen values being of course left to the skilled artisan as shown inlet deflector 19 extends upwardly a certain distance above the level of lower collector 17 and at least high enough to provide a first swirling at a to the path 11 of cooking fumes ascending into the illustrated exhaust hood 1 in the illustrated embodiment the top of inlet deflector 19 is located above the level of grease particles and impurities collector 29 which will.