Dangers of Metal Dust and Fumes

One does not always think about fumes when working with metal. (Why would you? It’s metal! It’s hard and quite solid, thank you very much.) However, both metal fumes and dust can be extremely hazardous to health with prolonged exposure.

But where would you find metal dust and fumes?

Metal dust and fumes are present wherever there is any metalwork going on. It includes welding, soldering, thermal cutting, sanding, polishing, buffing, engraving, brazing, grinding, deburring, among other things.

What Are the Dangers of Metal Fumes?

What Are Metal Fumes?

Metal fumes are the visible cloud of vapour that is generated when metals are heated to a very high temperature, like when you’re welding or soldering them. These fumes are 90%-95% particulate matter and 5%-10% gases.

How Do Metal Fumes Affect You?

Metal fumes are easily inhaled, causing dizziness and nausea. If you are exposed to them over a long time, even in small quantities, they can cause lung damage, and cancers of the lungs, larynx, and urinary tract. They also cause metal fume fever, stomach ulcers, kidney damage, and damage to the central nervous system. For example, Manganese fumes may cause symptoms similar to Parkinson’s disease.

If you’re welding metal that is plated, galvanised, or painted, you could generate Lead, Zinc, or Cadmium fumes, all of which are dangerous.

These are just the dangers of metal fumes. When welding or soldering, you can also be exposed to other types of vapours. These include colophony fumes (when soldering with a rosin core), Phosgene and Hydrogen Chloride gases (when welding in the presence of chlorinated hydrocarbons), Carbon Monoxide, Nitrogen Dioxides, and Ozone.

What Are the Dangers of Metal Dust?

Metal dust can be classified as inhalable or respirable.

Inhalable metal dust is made up of large, visible particles, between 100 microns to 30 microns, and sometimes smaller. What Anakin Skywalker said about sand is true for inhalable metal dust as well. It’s all coarse, and rough, and irritating. And it gets everywhere. It gets in your eyes, nose, and throat, causing discomfort to the various tissues.

Respirable metal dust is made up of smaller particles, around 1 micron to 0.1 microns. These are generally not visible and are more dangerous as they get into the alveoli in your lungs.

Both types of metal particles can cause long-term lung damage with prolonged exposure.

Siderosis is one such disorder that comes from breathing in iron dust. It is also known as welder’s lung or silver polisher’s lung.

Silicosis, another lung disorder, is caused by silica dust.

Fine metal dust isn’t just a health hazard. It is also extremely flammable, especially Magnesium dust. Moreover, it burns extremely rapidly at temperatures between 5000 to 8000 degrees F (2760 degrees C to 4426 degrees C).

You can’t put out a metal fire with water or commercial fire extinguishers. When water hits such high temperatures, it breaks down into Hydrogen and Oxygen, of which Hydrogen is highly combustible. In fact, Hydrogen burns so rapidly that it explodes. Even when it doesn’t break down, water heats up and becomes super-heated steam. Either way, it can cause more damage than the initial fire.

The best way to deal with metal dust fire is to prevent it from happening. This means removing any ignition sources, and collecting, storing, and removing it in a prescribed way.

How Do You Extract Metal Dust and Fumes?

Metal fumes and dust can be extracted using:

• Ambient collection
• Source Collection
• Hood Collection
• Down-flow Collection

Ambient collection involves removing the pollutants from the room. This is generalised extraction that can help keep the space free of vapours and particles but is not ideal for comprehensive extraction.

At-source collection is a better way to trap the fumes and dust at the source before they can get into the air. This is normally done with an arm that can be directed towards the source, where it sucks up the pollutants.

Hood collection is another method of preventing these particles from escaping, by covering the workstation with a hood that extracts the fumes and dust at the source.

Down-flow collection happens on a table with an open grid on the surface. The particulate matter is captured and extracted using suction.

At VODEX, we have several extraction solutions designed specifically for metal dust and fumes, including those from welding, soldering, grinding, and brazing.

We also offer HCM Heavy Duty Downflow Extraction Benches designed specifically for welding and grinding. You can tailor it to your needs, building on a basic model without an arm or filter, to one with a filter or arm or both. The bench comes with cartridge filters with fine fibre designed to catch particles of every size, including respirable dust.

If you want to know more about these benches, contact us. We will be happy to answer all your questions and tell you if this bench will be suitable for your application.