Prior to weling galvanized steel, try to remove as much of the zinc coating as you can with a wire brush, grinder, or a 50/50 mix of muriatic acid and water(can be found at any plumbing supplier for about 15 dollars) this reduces the risks of heavy metal poisoning. Drinking a Glass of milk prior to inhaling vaporized zinc will only mask symptoms of poisoning and could have profound effects on your health in the future. Stay Safe!