Always when I go into the hives. If I am just feeding them by filling or cleaning the hive top feeder, or checking out the entrances, then I don't wear protective clothes. My girls are really gentle, but when I worked this summer helping my mentor with his pollination contracts his girls are not nice at all. I removed fifty stingers from one glove, from one hive. I bought two suits, one for working with his bees and one for working with mine...