The Eyes

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The Eyes

• Industrial Hygiene
• IENG 431
• Dr. Carter J. Kerk
• Industrial Engineering Department
• SD School of Mines
• Spring 2009

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Assignment

• Read Plog, Chapter 5
• Anatomy Coloring Plates
• Study Plate 95-97
• Color Plates 95-96
• Due ?
• Read Vision Testing article
• Write a 2 page paper
• What did you learn, what surprised you?
• How important is vision in the workplace?
• How much attention does it currently get?

3
Outline The Eyes

• Anatomy of the eye
• Eye Problems
• Visual Performance
• Eye Disorders
• Physical Hazards
• Protective Equipment
• Vision Conservation Program
• AMA Guides to Evaluation of Permanent Impairment

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Introduction

• Although not the 1 route of entry for hazards,
  the eye may be the most vulnerable organ for
  occupational injuries
• The eyes are under great demand during work
• Issues
• Fatigue and discomfort
• Absorbing hazardous substances
• Flying chips and particles
• Lasers
• In 2004, 37,000 nonfatal occupational
  injuries/illness involving days away from work
  (BLS)

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Cross Section of EyeSagittal View
http//www.99main.com/charlief/Blindness.htmvxa
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Cross Section of EyeRear View
http//www.99main.com/charlief/Blindness.htmvxa
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Cut-Away View of Eye
http//www.99main.com/charlief/Blindness.htmvxa
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Lacrimal SystemProduction and Drainage of Tears
http//www.99main.com/charlief/Blindness.htmvxa
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The Retina

• Thin membrane lining the rear of the eye
• Contains light-sensitive cells Rods and Cones
• Rods More sensitive to light
• 120 million per eye
• Cones More sensitive to color
• 6 million per eye
• Less sensitive under low luminance

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Eye Specialists

• Ophthalmologist
• MD who specializes in vision
• Practices medicine and surgery
• Optometrist
• Doctor of Optometry (OD)
• Diagnoses, manages, and treats conditions and
  diseases of the eye
• Can prescribe certain pharmaceuticals,
  eyeglasses, contacts
• Optician
• Manufactures, verifies, delivers lenses

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Snellen Chart

• Test for visual acuity
• Visual Angle

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Eye Defects

• Farsightedness (hyperopia)
• Nearsightedness (myopia)
• Astigmatism
• Presbyopia

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Visual PerformanceDepends Upon

• Visual Acuity
• Luminance
• Position in the Field
• Duration
• Contrast
• Dark Adaptation
• Depth Perception
• Color Vision

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Eye Disorders

• Conjunctivitis
• Infections
• Uveitis
• Glaucoma
• Cataracts
• Sensitivity to Excessive Brightness
• Night Blindness
• Eyestrain
• Nystagmus

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Physical Hazards

• Blows from objects
• Corneal lacerations and abrasions
• Blink Reflex
• Foreign Bodies
• Thermal Burns
• Irradiation Burns
• Ultraviolet Radiation
• Infrared Radiation
• Visible Light
• We will do a separate presentation on
  Lasers/Radiation later

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Electromagnetic Spectrum
Electromagnetic Spectrum contains all the wave
energies that allow modern conveniences such as
cellular phones, medical x-rays, pagers, TVs, and
radios to operate.
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Chemical Hazards

• Caustics are more dangerous to the eyes than
  acids
• A caustic exposure might not look too bad on the
  first day, but could then deteriorate
  significantly
• Strong acids tend to precipitate a protein
  barrier that prevents further penetration

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ANSI Z358.1 - 2004

• Covers the design and function of eyewash
  fountains
• The book is outdated on this standard
• Purchase thru www.ansi.org
• Highlights
• Flush both eyes from airborne contaminants
• Nozzles protected from airborne contaminants
• Minimum flushing rate 0.4 gpm for 15 minutes
• Stay open-valves (for hands free use)
• Activation in one second or less
• Place within 10 seconds of hazard
• Identify location with a highly visible sign

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Protective Equipment

• ANSI Z87.1 2003 (book is out of date on this)
• Governs safety eyewear and face protection for
  occupational settings
• 29 CFR 1910.133
• OSHA Regulations on eye protection
• Impact Protection
• Spectacles
• Goggles
• Eye Protection for Welding
• Eye Protection for Lasers
• Sunglasses
• Use of contacts

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Vision Conservation Program

• Environmental Survey
• Vision Screening Program
• Remedial Program
• Professional fitting and follow-up procedures
• AMA Guides to the Evaluation of Permanent
  Impairment
• Table 5

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Reference

• Nims DK. Basics of Industrial Hygiene. John
  Wiley Sons, Inc., 1999.

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Assignment

• Read Plog, Chapter 5
• Anatomy Coloring Plates
• Study Plate 95-97
• Color Plates 95-96
• Due ?
• Read Vision Testing article
• Write a 2 page paper
• What did you learn, what surprised you?
• How important is vision in the workplace?
• How much attention does it currently get?

26
Assignment

• Read Plog, Chapter 5
• Anatomy Coloring Plates
• Study Plate 95-97
• Color Plates 95-96
• Due ?