Can Flux Core Welding Make You Sick?

The introduction of low-cost flux core welding equipment makes home and hobby welding attractive and affordable.  The convenience and ease of use of these machines open the world of metal welding to a vast new user community.  The opportunities for home metalworking enthusiasts are exciting. However, there are other considerations, including the question, can flux core welding make you sick?

The smoke and fumes from flux core welding can be toxic.  The products of flux core welding can have both short-term and long-term health effects.  Acute exposure to the fumes can cause eye, throat, and nose irritation.  Prolonged exposure can cause lung damage and may lead to much more serious chronic illness.

Metalworking and welding are fascinating skills enjoyed by professionals and hobbyists alike.  Most professional welders are aware of the hazards associated with welding fumes.  Unfortunately, most hobby welders don’t understand the dangers.   We’ll explain the hazards and the safety requirements of using flux core welders.

What’s in the Smoke – Knowing What you are Breathing is Important

According to OSHA, there are several hazardous materials in the fumes created by flux core welding.  Among these materials are:

  • Aluminum
  • Antimony
  • Arsenic
  • Beryllium
  • Cadmium
  • Chromium
  • Cobalt
  • Copper
  • Iron
  • Lead
  • Manganese
  • Molybdenum
  • Nickel
  • Silver
  • Tin
  • Titanium
  • Vanadium
  • Zinc

When vaporized and breathed in, many of these materials can pose serious health risks for welders.  In many cases, the exposure rates are enough that even occasional hobby welders face some risk.  Exposure to some of these materials is cumulative.  Even small exposures over time can result in symptoms of health problems.

What are the Dangers that Flux Core Welding Fumes Present?

Understanding what you may be breathing when you flux core weld and the possible side-effects of inhaling those fumes can be eye-opening for many home welders.  The flux core welding process generates hazards that most hobby welders don’t anticipate.

Getting Small – The Problems with Particles

Flux core welding involves high heat.  This heat, generated by an electric arc, melts the metal on the project hot enough to fuse two pieces of metal into one.  This high heat and electric arc also cause small particles of the welding wire, the flux, and the welded material to enter the smoke plume.  Particulates breathed in potentially can cause a variety of health issues.

  • Acute exposures can result in irritation to the eyes, nose, and throat.  Irritation to these areas can occur rapidly depending on the intensity of the exposure.  
  • Dizziness and nausea may also accompany these symptoms of acute exposure
  • Continued prolonged exposure can result in lung damage.  The particulates inhaled in the flux core welding fumes can lodge in the lungs leading to severe lung damage
  • Some metal particulates in the flux core welding plume can cause nerve damage.  Over time, this nerve damage can create Parkinson like symptoms.
  • Cancer of the lungs, larynx, and urinary tract are directly associated with the particulates contained in flux core welding fumes. 

Don’t Forget the Gases – The By-Products of Welding

The process of flux core arc welding also produces several gases of concern.  The high temperatures, electric arc, and ultraviolent light created by the arc can produce a mixture of gases.  Among these gases of concern are:

  • Ozone
  • Nitrogen dioxide
  • Nitric oxide

This trio of gases often causes eye, nose, and throat irritation.  Intense or long-term exposure can cause enough irritation in the lungs to result in fluid buildup resulting in other long-term pulmonary problems.

If the welded metal has a high chromium content or uses a chlorinated solvent for cleaning before welding, several potentially toxic gases may result.  

  • Phosgene, a highly toxic gas that acts on the nervous system
  • Hydrogen chloride that can result in dangerous irritation in the lungs and nasal passages
  • Chlorine gas that is both toxic and irritating

These symptoms of exposure may not happen immediately.  The effects may not appear for some time after the exposure.  In some instances, the effects of exposure to these materials may be cumulative and occur over long periods.  Symptoms may not appear until long after the exposure.

Protect Yourself – Take a Few Simple Precautions

There are protections that even hobby welders can employ to reduce their exposure to the hazards of breathing fumes from flux core arc welding.  For the most part, the easiest safety precaution is an awareness of the dangers that flux core welding can produce.

  • Understand the process and the dangers – A basic knowledge of the flux core welding process and the welding materials raise your awareness level. An awareness of the hazards you may face allows better planning and protection.
  • Weld only clean materials – Welding on dirty materials can produce toxic fumes with unknown materials.  Remove old paint or surface contamination before welding.  If you use a solvent to clean the metal, remove all traces of the solvent before welding.
  • Weld in a safe environment – Perform your welding tasks in a well-ventilated workspace.  If possible, arrange a fan to blow welding fumes away from you during your work.  Avoid welding in enclosed spaces where toxic fumes and gases can accumulate. 
  • Protect yourself adequately – Wear a high-quality welding hood.  If the situation necessitates, wear respiratory equipment to protect from inhaling welding fumes.

Don’t Forget the Other Welding Hazards

The fumes from flux core arc welding aren’t the only dangers you should consider.  Operating safely when using a flux core arc welder, don’t stop and protecting yourself from the fumes.   Always keep the other safe operating principles in mind.

  • Understand your equipment – Read the user manual.  Follow the manufacturer’s guidelines for operating your flux core welder.
  • Avoid electric shocks Flux core welders operated at high voltages that are potentially deadly.  An inadvertent short circuit or placing yourself in line with the voltage can have serious consequences.  
  • Don’t weld in the wet – The surfaces you are welding and the floor in your work area should be dry.  Water can be an excellent conductor of electricity.  Working in the wet, with wet materials and equipment, is an invitation for disaster.
  • Eliminate potential hazards in your work area – Many home hobby shops serve multiple purposes.  These multiple-use shops often contain materials that can become a serious hazard when welding.  Remove explosive or flammable materials such as gasoline, paint, and sawdust from the welding area.  
  • Wear your protective equipment – A good welding mask or shield will protect your eyes and head from splatter and UV rays.  Wearing a good leather welding apron can keep splatter from causing burns.  Proper welding gloves and long sleeves afford protection from the heat, splatter, and UV burns associated with flux core welding.
  • Keep your equipment in top working order – Following the manufacturer’s recommendations for maintenance and care of your equipment helps reduce the risks.  Use only those products that the manufacturer recommends and always follow the operating instructions. 

Get Informed and Stay Safe

For more information about flux core welding safety, consult these websites.

Occupational Safety and Health Administration – Controlling Hazardous Fume Gases During Welding

Occupational Health and Safety – Welding Fume and Gas Exposure

Lincoln Electric – Five Potential Welding Safety Hazards to Avoid

Staying Safe – The Key to Enjoying Welding and Metal Working

Welding and metalworking can be fascinating and enjoyable hobbies.  However, there are certain dangers as there are with any hobby that involves power tools or equipment.  Understanding the hazards and how to protect yourself are important to your long-term enjoyment.  

We hope that this article has added to your understanding of your flux core arc welding and the possible hazards it may bring.  Understanding these hazards allows you to take the proper precautions and enjoy your welding and metalworking hobby for years without problems.

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If you liked this article, have a look at my other articles I wrote about the topic!

Alexander Berk

A bit about myself: I am a certified international welding engineer (IWE) who worked in different welding projects for TIG, MIG, MAG, and Resistance Spot welding. Most recently as a Process Engineer for Laser and TIG welding processes. To address some of the questions I frequently got asked or was wondering myself during my job, I started this blog. It has become a bit of a pet project, as I want to learn more about the details about welding. I sincerely hope it will help you to improve your welding results as much as it did improve mine.

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