Arc eye
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Arc eye, also known as arc flash, welder's flash, corneal flash burns, or flash burns, is a painful ocular condition sometimes experienced by welders who have failed to use adequate eye protection. It can also occur due to light from sunbeds, light reflected from snow (known as snow blindness), water or sand. The intense ultraviolet light emitted by the arc causes a superficial and painful keratitis.
Symptoms tend to occur a number of hours after exposure and typically resolve spontaneously within 36 hours. The sensation has been described as having sand poured into the eyes.
This phenomenon results from intense levels of illumination, greater than that of more common over-illumination found in many factories and offices.
Flash burns can reach temperatures as high as 35,000° F. They are caused by an electrical arc or explosion near the body. An arc is a bright, luminous, electrical discharge through the air that occurs when electric current flows between two or more separated, energized, conducting surfaces.
The heat energy and intense light at the point of the arc is called arc flash. Air surrounding the arc is heated quickly and intensely. The expansion of water vapor in volume and the vaporization of metals causes a pressure wave which is called an arc blast. This explosion is comparable to that of dynamite.
Hazards as a result of arc flashes and arc blasts are:
- Thermal Radiation (Heat)
- Pressure Wave (Blast)
- Molten Metal (heated projectile)
Standards
Four principal standards govern [arc flash hazards]:
- OSHAStandards 29-CFR, Part 1910. Occupational Safety and Health Standards. 1910 sub part S (electrical) Standard number 1910.333 specifically addresses Standards for Work Practices and references NFPA 70E.
- The National Fire Protection Association (NFPA) Standard 70 - 2002 “The National Electrical Code” (NEC) contains requirements for warning labels.
- NFPA 70E 2000 provides guidance on implementing appropriate work practices that are required to safeguard workers from injury while working on or near exposed electrical conductors or circuit parts that could become energized.
- The Institute of Electronics and Electrical Engineers (IEEE) 1584 – 2002 Guide to Performing Arc-Flash Hazard Calculations.
Signs
- Intense lacrimation
- Blepharospasm
- Photophobia [link]
- Fluorescein dye staining will reveal corneal ulcers under blue light
Management
- Instill topical anaesthesia
- Inspect the cornea for any foreign body
- Patch the worse of the two eyes and prescribe analgesia
- Topical antibiotics in the form of eye drops or eye ointment or both should be prescribed for prophylaxis against infection
Resources
 [WikiProject MetalworkingWikiProject] Metalworking
| |
|---|---|
| Welding | |
| Arc welding: Shielded metal (MMA) | Gas metal (MIG) | Flux-cored | Submerged | Gas tungsten (TIG) | Plasma | |
| Other processes: Oxyfuel | Resistance | Spot | Forge | Ultrasonic | Electron beam | Laser beam | |
| Equipment: Power supply | Electrode | Shielding gas | Robot | |
| Related: Heat-affected zone | Weldability | Residual stress | Arc eye | Underwater welding | |
| See also: Brazing | Soldering | Metalworking | Fabrication | Casting | Machining | Metallurgy | Jewelry | |
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