Zink vaporizes at around 900C or 1600F. If inhaled the vapor can kill you. Galvanized steel is coated in zink and your RMH can exceed 900C in the heat riser.Welders and blacksmiths have done themselves in. In small doses zink vapor causes flu like symptoms. Attacks get worse with additional exposure. Skin and lung lesions and erratic behavior occur. Some have died with one exposure due to acute resperatory distress.

Wear an asbestos grade mask when welding galvanized pipe. Avoid galvanized materials in the heat riser. If you do use some galvanized pipe within the system, carefully discard the ashes from the first few firings as the zink settles there. Wear your mask.

Vapors are produced when using angle grinders and cutting wheels.

I went into several blacksmith forums and found that many amateurs were unaware of this risk.

My friend Randy died a few years ago of indeterminate causes. He had all of the symtoms I've read about including some very erratic behavior which resulted in some very cavalier disregard for his health. He couldn't get along with anybody including his young daughter near the end. He would make sweeping accusations etc. So far as I know, heavy metal poisoning was never determined. This all came to light yesterday while I was pursuing safety measures for welding. He was an amateur welder and blacksmith.

I used a section of galvanized ducting to hold insulation inside the heat riser. I figured that the resulting zinc oxide would all exhaust outside where it would dissipate harmlessly, but took precautions to avoid poisoning anybody the first few times the heater was fired. there is some more galvanized ducting further downstream that is exposed to the room, but it doesn't get anywhere near hot enough to be a problem.

anyhow, good PSA, Dale.

Well once again this comes up. please look at the temps in the system. the zinc is in the liner of the heat riser. the only bit that gets hot enough to cause zinc vapor As has been written before burn off the liner when you burn off the barrel. you arent going to be breathing the smoke from the barrel at any rate. yes if you huff the paint fumes and zinc it will cause problems in your system. Too much too fast and you die. Any welder can tell you the symptoms and how to help mitigate them if you happen to be huffing the exhaust in the first 10 min of burn (not what i recommend). If you dont want to use pipe in the heat riser then build it from brick or stainless. the material for the liner of the heat riser matters very little if you are using perlite and clay cause its going to burn out anyway. you can use a cardboard tube with an OD of 6 or 8 inches. Please dont get hung up on the materials, there are always options.

Ernie Wisner wrote:Well once again this comes up.

That's what she said

Well, I've been spanked. Only last week I wrote the following in the questions for Ernie and Eica thread------------- "Ernie dosen't suffer fools well. On several occasions he has asked people to read the older threads, to watch the videos and when they're seriously ready to build, he encourages them to buy the book. He has built over 700 units and has answered many questions over and over again.

Many of the answers are available simply by searching his postings and on his website. Let's do him the courtesy of educating ourselves so that we don't waste his time on stuff that has already been covered to death."

In my defense I did a search using the words zink and poisoning and nothing came up. That's what ..... I think anyone operating a forge is at far greater risk than those building stoves. I'm going to continue wearing a mask when I cut up oil tanks.

Dale Hodgins wrote:

Ernie Wisner wrote:Well once again this comes up.

In my defense I did a search using the words zink and poisoning and nothing came up. That's what ..... I think anyone operating a forge is at far greater risk than those building stoves. I'm going to continue wearing a mask when I cut up oil tanks.

just for kicks, Dale, try a google search for "zink."

Zinc will get a lot more matches than zink will.

My computer which was stolen dealt with spelling for me. I've been reduced to WiFi and a telephone. Ooops.