How Bright Is A Welding Arc Compared To The Sun?

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Welding is metalwork that involves a massive amount of heat to join and repair things. When we apply heat on metal pieces, an arc melts the metal and joins the two objects. The welding arc is bright as it comes from the massive amount of heat and electricity. It is expected that human eyes squint while looking at the sun and can’t open their eyes. It is also an unhealthy thing for human eyes.

Similarly, welding arc is intense that can harm the human eye. By standing next to the welding arc, you will also feel a burning sensation in the whole body. Its intensity can hit the optic nerves.

After knowing this, you may be curious to know about “how bright is a welding arc compared to the sun?”

The welding process produces massive heat, around 3400k, less than the sun heat, around 5800k. If you want to compare the brightness of the sun and the welding arc, then the sun is always a winner. Moreover, the radiated heat measurement is directly proportional to the temperature, and the sun has 8.4x more brightness than all objects.

This answer may or may not satisfy you. So let’s discuss all the related facts regarding the brightness of the sun and welding arc in detail.


How Bright Is The Sun?

As I already said that there is no competitor of sun brightness. It is the part of the world solar system that is the primary source of visible light and infrared radiation. However, if I talk about direct sunlight, it has 93 lumens per watt of radiant flux, which is highly luminous. Calculating the figures is 93 lumens per watt that refer to 1050 watts per square meter.

These figures represent that sunlight approximately provides the bright illuminance of 98000 lumens per square meter at sea level. It is a fact that sun illuminance at sea level is different than the dry places.

How Bright Is A Welding Arc?

The welding arc is hot and bright that helps the welders to join two metal pieces. It is hot enough that the human body feels in hellfire. Remember that welders can’t deal with the arc of welding without using personal protective materials, specifically without welding helmets or glasses.

You may think that it is bright enough like the sun but is it true? Did you ever compare their intensity?

Let me clear to you that the sun is brighter than the welding arc. No matter how intense it is but it can’t compete with the intensity of the sun. Welding arc produces massive heat that ranges up to 34000k, but the sun has way more heat, around 5800k.

Now the sun and welding arc brightness have a clear difference as nothing or technique on Earth produces the heat similar to the sun. Moreover, the sun is more prominent than Earth, so you can’t maintain the welding arc brightness identical to the sun.

How Intense Is A Welding Arc Compared To The Sun?

How Intense Is A Welding Arc Compared To The Sun

I hope it is clear that the sun is more intense than the welding arc. But if you still have the confusion, then let me clear it to you in another way.

Too much exposure to welding arc can burn the painful eyeball. We are 93 million away from the sun that is along with the distance. But the welder is a foot away from the welding arc that can burn the eyeball in less time.

Welding arc has less intensity than the sun, but it can still damage the welder’s naked eye. Sun can’t burn the eyeball as it is at a long distance with atmosphere and water vapour that weakens the sun’s brightness and intensity to damage the human eye.

We should, thanks to nature that it has an atmospheric layer that protects us from sun intensity; otherwise, a human body can’t survive.

Compared to the sun, a welding arc can cause sunburn but didn’t lead the welder to death. The welder can stand near the welding torch but never close to the sun as we didn’t survive there. The welding torch is small but produces intense heat that can burn human skin or eyeballs.

When Was Arc Welding Invented?

The welding arc is invented along with welding techniques in the 1800s. Russian scientist did their research and had control over the electric arc. Later, using the same concept, Russian inventors demonstrate how electric arc can join metal objects after this technique leads to arc welding.

What Types Of Radiation Are Associated With Welding?

Now you know that welding arc can’t come close to sun brightness. But still, the welding arc is bright and produces harmful UV radiations that require protective measures. It releases a specific value of UV radiation.

Welding torches use inert gas o weld the metal. Helium is the standard inert gas at 300A  that produces UVB and UVC radiation. These radiations cover a distance of one meter and harm the human body.

Welding arc produces UV radiations, infrared radiations, and visible light. It consists of three types of rays basing on their wavelength.

Here is the different wavelength range of radiations:

  • UVA that ranges between 315 to 400nm
  • UVB that ranges between 280 to 315nm
  • UVC that ranges between 100 to 280 nm

UVC has a shorter wavelength than other rays, but it is still harmful radiation from the sun and welding arc. The atmosphere layer filters the sun’s UVC rays before reaching Earth, so it doesn’t harm our bodies. Welders need to wear protective gear to protect their bodies.

UVB is medium wavelength radiation that can’t penetrate through our skin layer, but it doesn’t mean that it is an inactive form of radiation. It is active radiation that can harm the skin, like skin ageing, burning, and tanning. Moreover, it also causes skin cancer.

UVA radiations reach Earth after filtration through the atmosphere layer and deeply penetrate the human skin. It causes skin tanning, skin ageing, and wrinkling that also leads to skin cancer. Moreover, UVA can pass through the eye cornea and damage the eyes.

What Are The Symptoms Of “Arc Eye”?

UV radiations associated with welding arc and sun rays can damage the eye surface and mucous membrane. This damage is known as the arc eye, arc flash, and welders eye. It is dangerous to damage that welder face if they don’t wear welding helmets or other protective gear.

Moreover, arc eye is conjunctivitis that includes mucous membrane inflammation and becomes severe. The symptoms of arc eye include:

  • Painful eyes ranging from mild to intense pain
  • Redness and tearing of eye membrane that also refers to as the bloodshot
  • Light sensitivity
  • Unable to directly look at light source refers to as the photophobia
  • Sand sensation in the eye

Arc eye doesn’t appear with a single exposure to welding torch or technique. It depends on various factors like the intensity of UV rays, welding arc distance, angle of radiation that enters the eye, and usage of a protective layer. All these factors collectively affect the intensity of the arc eye.

Long-term exposure to radiations can heat the lens of the eyes and causes cataracts. However, the visible light can only push the blinding and eye fatigue as it is bright, and that eye doesn’t tolerate it. So with regular exposure, it can cause more severe issues for the welder’s eyes.

What Are The Skin Hazards Associated With Welding And Radiation?

Arc welding creates UV radiations that cause many skin hazards and lead to severe damages. Welders have a short distance for the welding arc that is dangerous for skin protection.

As I already mention, welding arc produces three forms of rays, including UV, UVB, and UVC, that can easily penetrate welder skin and increase skin cancer. Moreover, exposed skin of welder with welding rays lead them to skin burning, tanning, and many more. Many welders prefer to use preventive clothes that reduce the chance of skin hazards.

However, welding arc produces intense ultraviolet rays that are dangerous for welder skin, including their eyes, feet, and hands. Welders need to maintain the proper distance between the welding torch and their standing position to have minor damage.

Safety Recommendations To Prevent UV Radiation In Welding

Welding arc and sun produces radiation that can harm the skin, so it must use some protective measures. Welders need to protect their skin and health from the dangers of welding radiation.

Here I will share some essential safety measures that help you in your welding career and prevent health from UV radiations.

  • Always use safety glasses, helmets, welding boots, gloves, and leather cloths.
  • Ensure that you wear a full-spectrum sunblock that provides full coverage from UV radiations
  • Ensure that you must wear protective gear like headgear with UV radiation proof
  • Ensure that all bystanders must wear the protective gears
  • Install the screens and curtains to protect the safety of bystanders.
  • The welders need to receive regular dermatological training to protect against hazards.

Remember that UV radiation increases the risk of skin cancer, especially if someone has regular exposure to such radiations. Welders have chronic exposure to UV radiations, so they have increased skin cancer risks.

So I would recommend all the welders adopt safety measures to protect their skin and health from critical dangers.


So by summing up the above discussion, it is clear that the sun is brighter than the welding arc. But keep in mind that welding arc brightness includes dangerous radiations like UVC, UVB, and UC that can harm the welder’s skin and increase chronic diseases. It is essential to wear protective gear while standing next to the welding torch.

There is a protective atmosphere layer between the sun and Earth that protects humans from the sun’s dangerous UV rays, due to which they can’t harm human health.

I hope this article helps you understand how bright welding arc is and how it impacts the welders’ health.


[sc_fs_multi_faq headline-0=”h3″ question-0=”Why are welding torches so bright?” answer-0=”Welding torches are bright as they use a massive amount of heat and electric energy. It also releases harmful UV radiations that can affect the welder skin. Moreover, welding torches use Inert gas like helium that also increases their brightness. ” image-0=”” headline-1=”h3″ question-1=”How bright is an electric arc?” answer-1=”The electric welding arc is also bright with the intensity of flash 3 meters to 1 million lux. According to a recent test study, electric welding arc is 13.1 million lux which is 130 times darker than the traditional welding torches.” image-1=”” headline-2=”h3″ question-2=”How hot is plasma arc?” answer-2=”The hotness of the plasma arc depends on the temperature and electric power required to create a welding arc. It also depends on different factors that help to make the plasma—however; the traditional value of plasma jet torch temperature is 28000 Celsius or 50000 oF. The temperature of the plasma jet torch is less than the electric welding arc.” image-2=”” headline-3=”h3″ question-3=”Is welding hotter than the sun?” answer-3=”The welding procedure is not hotter than the sun. It produces the 3400K heat, whereas the sun creates the 5800 k heat. No heat can beat the level of the sun as it is 8.4 times brighter than the absolute objects. Heat is proportional to the object temperature and its fourth power. However, the sun is always a winner. ” image-3=”” headline-4=”h3″ question-4=”Is a welding arc brighter than the sun?” answer-4=”No sun is brighter than the welding arc. But it is bright enough to harm the human’s skin as it produces a lot of heat. A welder needs to take all the protective measures to prevent their skin from heat and UV rays of welding procedure. ” image-4=”” headline-5=”h3″ question-5=”If welding arcs are brighter than the sun, why don’t we use welding helmets to view solar eclipses?” answer-5=”Sun is brighter than the welding arc, and it is not wise to look at the solar eclipse without wearing protective glasses or a welding helmet. It helps to protect the eyes from dangerous sun rays. ” image-5=”” count=”6″ html=”true” css_]

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