Commercial dishwashers mostly needs a hood, but it may depend on the dishwater type and a few other points. For instance a commercial undercounter dishwasher will not require a dishwasher hood, while a door-type dishwasher will since it is a high capacity unit that will produce a big amount of steam.
Considering the size of your kitchen, if you are going to install it in a room with a high ceiling and enough ventilation a dishwasher hood will not be necessary. But if your kitchen has a small room with low ceilings, installing a hood or purchasing a dishwater vent will be very efficient. Otherwise the steam and heat will make the environment temperatures hard to work in. So there will be an uncomfortable place.