in some commercial settings they are used in conjunction with a bowl underneath which catches the drops as they fall. so they can drink out of that also. you could use them, they would use it; but you will need to provide them with something deep enough in addition that they can submerge their whole head in to clear out nares and eyes. such a thing could be provided for a period each day, maybe at days' end, to make sure they have a good clean out each day.
I have a 4 ft kiddy pool in the run for them in the summer but I was hoping to use the nipples inside during the winter. They splash so much water and the coop is always wet (not good for the chickens).