Video Displays, Work, and Vision -- Copyright -- Preface -- Contents -- Executive Summary -- 1 Summary of Findings -- INTRODUCTION -- Background -- Focus of the Study -- Organization of the Report -- The Literature Base -- The Nature of VDT Work -- FIELD STUDIES OF VDT WORKERS AND WORKSTATIONS -- Studies of Radiation Emission from VDTs -- Cataracts -- Field Surveys Based on Self-Reports of VDT Operators -- EQUIPMENT AND WORKSTATION DESIGN -- VDT Design and Display Quality -- Lighting and Reflections -- Human Factors -- THE CONCEPT AND STUDY OF ''VISUAL FATIGUE" -- JOB DESIGN AND PSYCHOSOCIAL STRESS -- DESIGN, PRACTICE, AND STANDARDS -- Principles of Good Design and Practice -- Public Education -- Standards and Guidelines for VDT Use -- RESEARCH NEEDS -- 2 Critique of Survey Methodology -- INTRODUCTION -- SURVEYS OF VDT USERS -- Adequacy of Theory -- Adequacy of Research Design -- Adequacy of Measurement -- Adequacy of Sampling -- Unanswered Questions -- RESEARCH DESIGN CONSIDERATIONS -- Control and Choice in Studies of VDT Physical Parameters -- Practical Considerations -- 3 Radiation Emissions and Their Effects -- TYPES AND LEVELS OF RADIATION EMITTED BY VDTS -- Studies of Emission Levels -- The 1977 NIOSH Study -- The Bell Telephone Laboratories Study -- A Collaborative Study -- Two European Studies -- The 1981 NIOSH Study -- The Bureau of Radiological Health Study -- Radiation Safety Standards -- VDT Emissions and Ambient Radiation -- BIOLOGICAL EFFECTS OF RADIATION -- Ionizing Radiation -- Nonionizing Radiation -- Ultraviolet Radiation -- Visible and Infrared Radiation -- Radio Frequency Radiation -- Skin Rashes -- VDT USE AND CATARACTS -- Prevalence and Causes of Cataracts -- The Evidence Regarding VDT Use and Cataracts -- The Claims -- Response to the Claims.

Methods of Studying Whether There Is a Relationship Between VDT Use and Cataracts -- Concurrent Longitudinal Study -- Nonconcurrent Longitudinal ("Cohort") Study -- Case-Control Study -- Two Ongoing Studies -- The NIOSH Baltimore Sun Study -- The Mt. Sinai Study -- Conclusions About Radiation Hazards -- 4 Display Characteristics -- EFFECTS OF CRT DISPLAY VARIABLES -- Luminance -- Effects on Visual Acuity -- Effects on Flicker Threshold -- Effects on Visual Task Performance -- Luminance Uniformity -- Contrast and Contrast Polarity -- Raster Structure -- Resolution -- Jitter and Temporal Instability -- Refresh Rate and Persistence -- Color -- Reflection Characteristics -- A Summary Measure: Modulation Transfer Function -- DISPLAY MEASUREMENT: TECHNIQUES AND PROBLEMS -- Measurement Techniques -- Measurement of Various Parameters -- Character Luminance -- Character Contrast -- Blur, Resolution, and MTF -- Reflection Characteristics -- Standardization -- FLAT-PANEL DISPLAYS -- Dot-Matrix Display Variables -- Character Size Effects -- Character Formation -- Contrast -- Font -- Luminance Uniformity -- Information Density -- Dot-Matrix Display Quality Measures -- Advantages and Disadvantages of Flat-Panel Displays Compared with CRTs -- FILTERS FOR VDTS -- Kinds of Filters -- Circular Polarizer with Antireflection Coating -- Neutral Density Filters -- Notch or Color Filters -- Directional Filters -- Evaluation of Filters -- General Comments -- Effectiveness of Filters -- 5 Lighting and Reflections -- ILLUMINATION -- Transient Adaptation -- Reflections -- Glare -- REVIEW OF VDT STUDIES -- Field Surveys of VDT Workers -- Field Surveys Comparing VDT and Non-VDT Work -- Laboratory Studies -- 6 Anthropometry and Biomechanics in VDT Applications -- POSTURAL STRAIN -- OVERVIEW OF BIOMECHANICAL FACTORS -- Work Posture -- Muscular Load -- Joint Angles -- Anthropometry.

WORKSTATION DESIGN -- Effects of Chair Design Features on the Spine -- Effects of Working Height on Postural Strain -- Effects of Display Position on Postural Strain -- 7 Visual Tasks, Functions, and Symptoms -- VISUAL ISSUES IN VDT STUDIES -- Field Surveys -- Visual Complaints -- Measurements of Visual Status -- Experimental Field and Laboratory Studies of Visual Functions in VDT Work -- The Need for Job and Task Analysis -- Are There Unique Features of VDT Tasks? -- The Special Task of Reading -- The Problematic Concepts of "Visual Fatigue" and "Eyestrain" -- Refractive Errors and Visual Difficulties -- Myopia -- OCULOMOTOR FACTORS AFFECTING VISUAL PERFORMANCE -- Eye Movements -- Saccadic Trajectory -- Dual Mode Tracking Eye Movements -- Higher-Level Eye Movement Patterns -- Reading -- Picture Scanning -- Gaze and the Vestibulo-Ocular Reflex -- Blinking -- Triadic Near Reflex: Combined Focusing, Convergence, and Aperture Mechanisms -- Accommodation -- Dynamic Factors in Accommodation -- Fatigue and Accommodation -- Vergence -- Pupil -- Pupil as a Regulator of Light Level -- Pupillary Constriction Associated with Prolonged Visual Work -- Pupil as a Factor in Visuomotor Discomfort -- Pupillary Hippus in Relation to Habituation and Sleepiness -- Synkinesis of Accommodation, Vergence, and Pupillary Constriction -- SUMMARY AND CONCLUSIONS -- 8 Job Design and Organizational Variables -- INTRODUCTION -- Workers' Complaints and Job Structures -- Defining Psychosocial Stress and Strain -- A FRAMEWORK FOR STUDYING PSYCHOSOCIAL STRESSORS IN VDT WORK -- Person-Environment Fit -- Objective and Subjective Fit -- STRESSORS FOR STUDY IN VDT WORK -- Control -- Opportunity to Control: E -- Need for Control: P -- Participation -- Opportunity to Participate: E -- Need to Participate: P -- Predictability and Controllability -- Unpredictable Events: E.

Tolerance of Unpredictability: P -- Complexity -- Role Ambiguity -- Threat of Unemployment -- Quantitative Workload -- Prescription for Overload-Deadline Plus Delay -- Responsibility for Persons -- Responsibility: E -- Responsibility: P -- Role Conflict -- Social Support -- DISCUSSION AND CONCLUSIONS -- 9 Design, Practice, and Standards for VDT Equipment and Work -- PRINCIPLES OF GOOD DESIGN AND PRACTICE -- Image Quality and Display Design -- Lighting and Reflections -- Minimizing Problems Caused by Direct Glare and Transient Adaptation -- Minimizing Reflected Glare and Veiling Reflections -- Systematic Design of VDT Workstations -- General Considerations -- Specific Design and Use Guidelines -- Job Design and Organizational Variables -- Variation in the Task and Task Environment -- Other Strategies for Good Employee Management -- STANDARDS AND GUIDELINES FOR VDT DESIGN -- 10 Research Needs -- EFFECTS OF DISPLAYS ON VISUAL ACTIVITY -- Objective Correlates of Visual Complaints -- Relating Display Characteristics to Workplace Conditions -- Effects of Image Instability -- Distinguishing Specific Effects of VDTs -- PSYCHOSOCIAL STRESSORS -- Appendix A A Review of Methodology in Studies of Visual Functions During VDT Tasks -- Appendix B Review of a Preliminary Report on a Cross-Sectional Survey of VDT Users at the Baltimore Sun -- SUMMARY OF THE NIOSH STUDY -- REVIEW OF THE NIOSH STUDY -- Study Approach and Methods -- Introduction and Background -- Design -- Measures -- Analyses -- Conclusions -- Substantive Conclusions -- Methodological Conclusions and Limitations -- Appendix C Dissent -- Appendix D Biographical Sketches of Panel Members and Staff -- REFERENCES.