Galvanized steel is a metal that is widely used in the metal fabrication industry. And if you have ever welded this type of steel you know how unpleasant it is. More importantly, welding galvanized steel can cause what is called galvanized poisoning.
So what is galvanized poisoning and what are the symptoms of galvanized poisoning? Well, let’s dive into the unpleasant world of welding galvanized steel and its toxic aftereffects.
About Galvanized Steel
But first, what is galvanized steel? This is a type of steel that has a layer of zinc coating applied to it. This zinc coating can also be applied to iron in a process known as galvanization. The zinc coating is applied to protect the steel or iron from corrosion.
The zinc layer forms a barrier between corrosive elements and the base metal. While this coating makes the metal resistant to rust and corrosion it also makes it hard to weld. When welded, the zinc coating produces a noxious gas that when inhaled causes galvanized poisoning.
This noxious gas is zinc oxide which forms when the zinc coating evaporates from exposure to high welding temperatures.
Signs Of Galvanization During Welding
When welding there are several signs that indicate galvanization. The number one sign is a yellowish-green smoke from the weld. If you see this kind of smoke it is a sign of galvanization and the production of zinc oxide.
Another sign is the appearance of a white powdery residue on the weld metal. You may also notice white particles in the air while welding.
Symptoms of Galvanize Poisoning
Inhale this yellowish-green smoke will result in galvanized poisoning. How long you have been exposed to the fumes will determine how bad the symptoms will be. So what are the general symptoms of galvanized poisoning?
- Flu-like symptoms include nausea and a headache when exposed to zinc oxide gas. These are usually the first symptoms after exposure.
- Moderate exposure will result in chills, shaking, and a slight fever. You will also experience vomiting and cold sweats.
At first signs of galvanized poisoning, you should stop welding immediately and get some fresh air. The symptoms will worsen with prolonged exposure to zinc oxide gases.
Treatment of Galvanize Poisoning
Luckily for us galvanize poisoning isn’t a serious condition and the symptoms will subside after 24 to 48 hours. Thus there isn’t a prescribed treatment. However, it is advisable to drink milk as the milk’s calcium content helps get rid of the zinc buildup in your body.
Drinking lots of water is recommended. On average the symptoms take between 24 to 48 hours to subside. While severe cases are rare they do occur due to prolonged exposure to the fumes. In such scenarios, the patient may require intravenous hydration and supplemental oxygen.
Are there any long-term effects or complications of exposure to zinc oxide? Studies done by both the CDC and the OSHA indicate that there are no long-term effects. Thus there aren’t any long-term health complications associated with exposure to zinc oxide.
How to Prevent Galvanize Poisoning
While galvanizing poisoning isn’t a serious condition it is still an unpleasant one and it is wise to know how to minimize the chances of being exposed to zinc oxide fumes. So how can you minimize the risk of exposure?
Remove the Zinc Layer
The first thing to do is to remove the zinc coating on the metal before welding. There are two methods of galvanizing steel, hot-dipping, and spray-on. If the zinc is sprayed on then it will be easier to remove.
Zinc coating applied using the hot-dipping method will be harder to remove. Nevertheless, in both cases, a grinder will be useful in removing the coating. An alternative will be to use coarse sandpaper.
After grinding the coating use a dry cloth to wipe the metal and remove zinc fillings that may be on the surface of the metal.
Use Protective Gear
Sometimes it may be impossible to remove the entire zinc coating on a metal. Therefore it is also important to wear protective gear. Most important when welding galvanized steel is a respirator and a helmet covering the respirator.
Do not use masks as they cannot protect you from the fine particles of zinc oxide fumes. If you are to use a mask using one with carbon filters and approved for welding.
Welding of galvanized steel should be done outside. However, if this is not possible ensure you are welding it in a properly ventilated room. Most welders who have suffered from this condition have done so while welding in a poorly ventilated area.
Use A Stick Welder
If it is safer to weld galvanized steel outside then it makes sense to use a stick welder on galvanized steel. Stick welders offer better penetration on galvanized steel than other types of welders. And of course, you can use a stick welder outside.
Good and bad foods for heavy metal poisoning
When exposed to heavy metals the foods you take will have an impact on the healing process. Foods high in vitamins should be top of your list of foods to consume. Foods such as garlic, lemon water, chlorella, and barley grass juice powder contain vitamins and minerals that help with the healing process.
Taking supplements to increase your daily intake of vitamins is also recommended. Vitamins B, B-6, and C are known to be good for heavy metal exposure.
So what foods should you avoid? The number one foods to avoid are processed foods and fats. These have very little nutritional value. Also, excess fats can slow down the healing process. This is because fats soak up the toxins you are trying to get rid of from your body.
Other foods you should avoid include rice, in particular brown rice. This is because brown rice often has arsenic. Some fish species especially larger and long-living fish. These contain more mercury than small fish.
You should also avoid alcohol if you have been exposed to any heavy metal. Nonorganic foods are also to be avoided.