Zinc hot dip is a different thing than baked on powder coating.
Fun story:
When I worked as a chemist at Virginia Chemicals one of our plant units was the "Vir-dust" plant. Many Virginia Chemicals products start with Vir or Va
(anyone remember Vapona? See footnote).
Virdust was used for applying a zinc coating to metals with the aid of metallic sodium. The sodium was melted and sprayed as a fine mist in a chamber of nitrogen ( It would explode if done in air). The solidified fine particles fall into the hopper where they are tumbled with super-fine zinc dust. All this is done under pure nitrogen. The zinc coats the sodium making it unreactive to air. The virdust was packed into barrels and used in a coating process similar to galvanizing, but with a much stronger bond to the metal.
OK, now to the fun part - The sodium was shipped in 55 gallon removable top drums is 2 pound blocks. The drums were filled with mineral oil. This kept the sodium form bursting into flame by exposure to air. Sodium is the second most reactive metal, with lithium the most reactive. When a barrel was empty, there was always some sodium sludge or smashed blocks in the bottom. When working during the winter, it was dark by 5, so at the end of the day we would take these "dregs" out wearing rubber gloves, mold it into balls. and throw them out on the river. Sodium is lighter than water, so it would skip around on the surface as a ball of fire. With ten or so running around on the water, it was eerie in the dark. It looked like something from a science fiction movie. Eventually, the Coast Guard figured out who was causing the "Strange Lights" seen over the river and told us to cut it out.
Footnote:
Vapona was a product packaged by Virginia Chemicals. It was a mixture of kepone and Malathion, use in different concentrations by professional exterminators and the Military. They purchased the kepone from Allied Chemical/Life Sciences.
Super powerful stuff on crawling bugs and termites, and it stayed active in the soil for decades. Problem was that kepone was a really bad chemical. Life Sciences had its plant near Richmond, VA where from the mid 1960's to the late 1970's the contaminated waste water from the manufacture was discharged in the James River. Once the bad effects on humans and animals were discovered, the plant was shut down, but the damage was done. The heavier than water kepone contaminated the river bottom for decades, and ended the famous Virginia oyster, fish, and crab industry. The seafood industry has returned to safe long since, but has never been the same. Virginia oysters used to be considered the best in the world. They are still good ( had a dozen or so last night), but once a reputation is soiled it never really gets clean again.
Vapona is still made and sold today by Bayer Animal Healthcare, It is supposedly a different formula, similar to RAID, and is for flying insects around and on animals ( cattle and horses). I think Bayer probably bought the chemical manufacturing part of VAChem when the company broke up. The product was popular, so they kept the name.
VAChem also packaged a form of vapona with 1% kepone mixed wit 99% DEET. This was supposedly a safe level of kepone. The testing said it was safe, but the military did the tests, so who knows how safe it really was. The same military labs tested Agent Orange and said it was OK, too.
It was used for the military in Vietnam as a fly/mosquito/lice spray on the soldiers. The soldiers would cover themselves and their clothes with it, and it lasted for weeks. It became a popular cattle and livestock spray afterwards. This is what the current vapona is used for, but the formula is supposedly completely different.
I bet there are many Vietnam vets on the forum who remember those green spray cans that were handed out by the dozens.
