“Arc Eye” and “Flash Burn”

Electromagnetic energy given off by an arc or flame can injure workers’ eyes and is commonly referred to as raidant energy or light radiation. The intensity of light or radiant energy produced by welding, cutting or brazing operations varies according to the number of factors including the tasks producing the light, the electrode size and the arc current.

1
Certain types of UV radiation can produce an injury to the surface and mucous membrane (conjunctiva) of the eye called “arc eye,” “welders’ eye” or  “flash burn.” The symptoms include:

  • pain – ranging from a mild feeling of pressure in the eyes to intense pain in severe instances
  • tearing and reddening of the eye and membranes around the eye
  • sensation of “sand in the eye” or abnormal sensitivity to light
  • inability to look at light sources (photophobia)

The amount of time required to cause these effects depends on several factors such as the intensity of the radiation, the distance from the welding arc, the angle at which the radiation enters the eye, and type of eye protection that the welder or bystander is using. However, exposure to just a few seconds of intense UV light can cause arc eye. These symptoms may not be felt until several hours after exposure. Long-term exposure to UV light can produce cataracts in some persons.

2
For protection from radiant energy, workers must use personal protective equipment, such as safety glasses, goggles, welding helmets or welding face shields. This equipment must have filters lenses with a shafe number that provides the appropriate level of protection. A shade number indicates the intensity of light radiation that is allowed to pass through a filter to one’s eyes. Therefore the higher the shade number, the darker the filter and the less light radiation that will pass through the lens.

(Today’s post comes to us courtesy of Al Rainsberger, CHMM for Foss Maritime)


Safety Consideration for Welders

Having recently redesigned our e-commerce website, we tried to make sure that our menu got you where you needed to be. Easier said then done!

A perfect example presented itself in the issue of welding. Now our site has a “welding” section but welding also could appear under “Respiratory Protection“, it could appear under “Gloves“, it could appear under “Eye Protection”, etc…

FlexView-Down

This got me thinking about what exactly as the health and safety issues that welders need to be aware of. I came up with the following list, if there are others that I’m missing please add them in the comments below:

  1. Respiratory Protection – As already mentioned welding entails fumes and particulates that shouldn’t end up in our lungs.  Make sure you understand what harmful fumes, vapors or particulates you need to protect against in order to have the proper filters or respiratory setup.
  2. Heat – Welding can generate temperatures that reach 10,000 degrees Fahrenheit. Make sure you have the proper welding gloves and apparel. You also need to be aware of slag and hot debris that can fly off and end up burning  (any welder who’s had hot slag down their back understands what I’m talking about). Heat can also start fires so make sure that the area around where you’re welding is clear of trash or debris that might ignite.
  3. Eye Protection – Most types of welding require special eye protection. Make sure you understand what shade of lens you need before you start welding. Burned retinas can be the price if you make a mistake.
  4. Hearing Protection – Aside from the noise involved with the welding itself, many welders work in high noise environments. It might not be the most comfortable thing in the world to have to wear hearing protection under that welding helmet but it’s a whole lot better than tinnitus or hearing loss later.
  5. Electrical Issues – Most forms of welding operate on the principle of creating an electrical short that melts metal to form a bond. Make sure you understand the process and understand grounding and what to avoid touching.
  6. Ergonomic Issues –  A lot of welding work is done in tight places or in positions that can wear on the welder.  Knee pads, back supports as well as other ergonomic equipment might be needed.

What am I missing?


The Basics of Welding Safety (Part 5)

Electrical Safety Issues

The basic principles of welding involve electrical current that is essentially being shorted at the tip of the welding rod to produce the heat needed to melt the rod and the steel long enough for them to bond and create the weld. This means, of course, that we are dealing with electrical current and that certain precautions must be taken in order to work with that current without danger.

  1. Both the electrode, as well as the work are hot (have electricity running through them) and must never be touched with bare skin or with anything that is wet.
  2. In semiautomatic or automatic wire melding almost all of the equipment (wire, electrode, reel, welding head and nozzle) is hot and should be treated with caution.
  3. Always make sure that your work is properly ground and that there is a good electrical connection with the metal being welded. The connection should be as close to the area being welded as possible.
  4. Make sure that all equipment is in good working condition. Remove and replace any frayed or faulty equipment.
  5. Never touch equipment from two different welding units as your body could create an electrical bridge and cause electrocution.
  6. Never work on any of the equipment until it has been disconnect completely. Never try to fix it while it is still hot.
  7. Always turn off all equipment when not in use.
  8. Make sure all equipment is installed and running according to code.

 

 


The Basics of Welding Safety (Part 4)

Arc Ray Safety

Arc Rays can cause retinal burns and eye injuries. The following chart, available from AWS (The American Welding Society) and available for free download here, outlines the different shades needed for specific types of welding.

The proper eye protection, however, does nothing if not worn when needed and properly.

Auto-darkening lenses (also known as auto-darkening filters or ADFs) are lenses that allow you to see without lifting your helmet but that instantly darken to the preset shade within a millisecond after the arc is struck, allowing the welder to have eye protection at all times. Fixed shade lenses on the other hand mean that the welder must raise his helmet to see whenever there is no arc. This means that the odds of eye and face injury increases.


The Basics of Welding Safety (Part 3)

Heat/Burns/Fire

Welding is hot work! Temperatures can reach 10,000 degrees F. To make matter worse, flux, metal particles and other super heated “bits” can be skipping or flying around as a result of the welding process. This means, of course, that the danger of burns and fires increases dramatically.

Certain precautions therefore have to be taken in order to avoid burns. Bare skin is, of course, not recommended. Flame retardant and fire resistant clothing is necessary. In addition, a certain number of other issues have to be taken into consideration:

  • No pockets – With flying super heated debris flying around, pockets are a hazard. Hot pieces can land inside a pocket and burn without being able to fall away.
  • Buttoned up collars – Keeping flying debris out of the neck line is essential
  • Shirts outside of the pants – Tucking the shirts inside the pants creates the same type of issue that pockets do. Shirts outside of the pants allow the hot particles to fall away rather than simmering.
  • Pants without cuffs – Cuffs end up essentially being the same thing as pockets.
  • Flammable and combustible material needs to be far from the welding area. Sparks and debris can be projected up to 35 feet or more.
  • The rules above about clothing apply to co-workers and others who might be in the immediate vicinity
  • Know the location of the fire extinguishers before you start working. Once a fire is blazing, it’s too late to go looking for it. Be prepared.

Heat issues

When dealing with temperatures that can reach 10,000 degrees, and complete skin coverage, especially with FR clothing, we are automatically talking about the possibility of heat stress. Understand the symptoms and treatment of heat related health issues and take the appropriate measures. Make sure that you take frequent breaks away from the heat and stay hydrated at all times.

Burns

If burns do occur, follow the proper burn treatment procedures. Water Jel is a great product for treating minor burns. Keep first aid burn products close by and know where they are.


The Basics of Welding Safety (Part 2)

Yesterday we outlined the 5 areas of safety that need to be addressed in order to make sure that welding stays safe.

We started by looking at one of the least considered ones, noise. Today we are going to look at the most common one, respiratory/Fumes

Fumes/Respiratory

Fumes and gases are the most obvious hazard associated with welding. Many of the metal give off fumes that are immediately noticeable and can cause burning of the eyes, skin irritation and rashes, nausea, vomiting and dizziness.

Other particles, fumes and gases can have a cumulative effect with symptoms not showing up till much later. Pulmonary and respiratory problems can result. Bronchitis, lung fibrosis and emphysema are just three of the possible long-term health problems that can develop over time.

As in all respiratory problems, engineering should always be the first line of defense. Ventilation and/ or exhaust should be used to “suck up” the fumes or circulate the air. A welding fume extractor provides ventilation directly at the source of the fume in order to keep the fumes and gases from dissipating. Because it extracts the fumes and gases right at the source, it substantially extends the life of the respirator cartridge as well as providing better protection for others who might be in the vicinity.

Procedures to protect yourself from welding fumes and gases:

  • Keep your face away from the fumes
  • Make sure that you can see properly. Don’t lean closer because you can’t see well. Use corrective lenses if necessary.
  • Use adequate ventilation. If indoors, use a welding fume extractor or other ventilation. If outdoors, natural ventilation may be adequate.
  • Wear respiratory protection where necessary. Powered Air Purifying Respirators (PAPR) are often the preferred form of respiratory protection in areas where fume extraction is not possible or feasible.
  • Understand the particular hazards associated with the metal or alloy you are welding. Cobalt, Zinc, Nickel (including nickel plated), Manganese, Copper and Silica all have special hazards that you need to research and be aware of before you start heating them up or welding on them.
  • Be aware of oxygen displacement. Even gases which might not be harmful in and of themselves can become hazardous if they are present in large enough quantities to displace oxygen. A basic 4-gas monitor might be necessary in order to adequately warn of oxygen displacement.

The Basics of Welding Safety (Part 1)

The new Hexavalent Chromium standard, as well as other welding related respiratory issues have been at the forefront of safety related issues long enough for most of us to be aware of some of the hazards associated with welding.

Respiratory protection issues, though certainly important, are by no means the only hazards to be aware of when looking at welding. Today and in the next couple of days we are going to be looking at the hazards associated with welding and how to make sure that welding is safe.

The hazards associated with welding include:

  • Noise
  • Fumes/Respiratory
  • Heat/Burns
  • Ultraviolet Radiation
  • Electrical Safety Issues

Noise

While Noise probably isn’t the first safety hazard most people associate with welding, there are good reasons to consider the issue. Arc welding equipment, as well as the generators and the actual noise generated by the welding process all combine to produce noise levels above the 85 dB threshold. Extended exposure to this high level of noise can and does, result in partial or complete hearing loss over time.

If in doubt, purchase a simple 3M Noise Indicator. It flashes green when noise levels are below 85 dB and red when the noise levels exceed it. Other options include sound level meters and noise dosimeters. You can also opt to have an Industrial Hygienist come in and monitor noise levels for you.

An additional consideration regarding ear plugs or ear muffs is the added protection that they afford for the ear canal. Flying sparks and metal pieces can easily bounce into the ear canal causing substantial pain and injury. Whatever form of hearing protection you use, you are also plugging the ear canal and keeping hot sparks and metal pieces out.


Construction Industry Lens Shades for Radiant Energy

Construction Industry Requirements for Filter Lens Shade Numbers for Protection Against Radiant Energy

 

Welding Operation

Shade

Shielded metal-arc welding

1/16-, 3/32-, 1/8-, 5/32-inch diameter electrodes

10

Gas-shielded arc welding (nonferrous)

1/16-, 3/32-, 1/8-, 5/32-inch diameter electrodes

11

Gas-shielded arc welding (ferrous)

1/16-, 3/32-, 1/8-, 5/32-inch diameter electrodes

 

12

Shielded metal-arc welding

3/16-, 7/32-, 1/4-inch diameter electrodes

 

12

5/16-, 3/8-inch diameter electrodes

14

Atomic hydrogen welding

10 – 14

Carbon-arc welding

14

Soldering

2

Torch brazing

3 or 4

Light cutting, up to 1 inch

3 or 4

Medium cutting, 1 to 6 inches

4 or 5

Heavy cutting, more than 6 inches

5 or 6

Gas welding (light), up to 1/8-inch

4 or 5

Gas welding (medium), 1/8- to 1/2-inch

5 or 6

Gas welding (heavy), more than 1/2-inch

6 or 8

 

Source: 29 CFR 1926.102(b)(1) (www.OSHA.gov)


 


Chart for Lens Tint for Protection against Radiant Energy

Operation

Electrode Size in Arc Current 1/32″ (0.8mm)

Arc Current

Minimum * Protective Shade

Shielded metal

arc welding

< 3

3-5

5-8

> 8

< 60

60-160

160-250

250-550

7

8

10

11

Gas Metal arc Welding and Flux cored arc welding

 

< 60

60-160

160-250

250-500

7

10

10

10

Gas Tungsten arc welding

 

< 50

50-150

150-500

8

8

10

Air Carbon

Light

< 500

10

Arc Cutting

Heavy

500 – 1,000

11

Plasma Arc Welding

 

< 20

20-100

100-400

400-800

6

8

10

11

Plasma Arc Cutting

Light **

Medium **

Heavy **

< 300

300-400

400-800

8

9

10

Torch Brazing

   

3

Torch Soldering

   

2

Carbon Arc Welding

   

14

 

Operations

Plate Thickness

Minimum * Protective Shade

Light Gas Welding

< 1/8 ” (3.2mm)

4

Medium Gas Welding

1/8″- ½” (3.2-12.7mm)

5

Heavy Gas Welding

> ½” (12.7mm)

6

Light Oxygen Cutting

< 1 (25mm)

3

Medium Oxygen Cutting

1-6″ (25-150mm)

4

Heavy Oxygen Cutting

> 6″ (150mm)

5

* As a rule of thumb, start with a shade that is too dark to see the weld zone. Then go to a lighter shade which gives sufficient view of the weld zone without going below the minimum. In oxyfuel gas welding or cutting where the torch produces a high yellow light, it is desirable to use a filter lens that absorbs the yellow or sodium line in the visible light of the (spectrum) operation.

 

** These values apply where the actual arc is clearly seen. Experience has shown that lighter filters may be used when the arc is hidden by the work piece.

 

Source: 29 CFR 1910.133(a)(5). (www.OSHA.gov)