Safety factors in welding galvanised steel

Quite true unless operator is wearing an approved respirator, or adequate ventilation is provided. You can end up with the 'Zinc Flu'. Had it before makes you big time sick. Restoring the protection is simply applying a zinc coating back on it after cleaning it real well.

Thanks "guest" much appreciated, Cheers, Tim

Hello timpatco, Tim,

The fumes emitted from any welding of Zinc coatings are extremely toxic to the operator and bystanders.

We used to use a fume hood, which surrounded the work, allowing the worker inside the fume hood, to do the cutting or welding.

Extractor fans took fumes away, and blew the fumes then through a water bath.

What used to come out of the water bath after a week's welding/cutting, was what would have otherwise ended up in someone's lungs, to poison them.

Even using a disk or other grinder will place an air suspension of metal dust plus metal oxides dust into the air, so ventilation per fume hood to water bath plus respirator for the grinder operator is required.

After the welding is completed, we used to give 3 coats of cold galvanizing zinc rich paint, allowing a full day between coats.

Remember that zinc-rich paint is very thick, and must be regularly stirred to keep the zinc-rich materials suspended, otherwise you end up with a thin coat of just solvent and pigment, which will not last.

When painting with zinc-rich paints, it is important use an organic chemicals mask, and also fire precautions, because most are 80% Xylene (Xylol) solvent based (Organically Toxic and Flammable).

Before painting, remove all welding slag, then warm the steel to dry it, about 110 degrees Celsius, ensuring no moisture remains in/on the work, then paint while still warm: This gives maximum protection.

Here I have steel with 3 coats zinc-rich paint, no rust or corrosion after 40 years, in salt-water marine environment.

Hope that assists you.

Kind Regards....

Hi Sparkstation

Thanks very much for that, as I was told and expected, nasty stuff indeed. I will now get a ruling from the relevent OHS site in Australia, Cheers, Tim

Once you have experienced the "FEAVER" you will never weld over Galvanize again, unless your wearing scuba gear. Watch out for Aluminum and copper alloys too. There get ya.

My Dad is fairly sure that repeated galvanized flu, as a teen is what is killing him with a very rare form of emphysema. 2nd known case. 16 dollars a weld job for a poor teen taking care of his Grandmother in the early 50's was the incentive.

Tough SOB the Docs said he would be dead in 5 months 15 years ago. Finely had to retire last year and still does more that most.

So if you can weld it first then galvanize it, if not take care.

2bits from

Brad