Design Error Most people look like this... Some designers think that people look like this...

What is Ergonomics? The study of man's relationship with his workplace. Fitting the task to the man rather than forcing him/her to adapt to his working environment. Designing the workplace to prevent occupational injury and illness. Discovering the capabilities and limitations of the human body.

Balance for Optimization Ergonomics Worker Capabilities Job Demands

CUMULATIVE TRAUMA DISORDERS (CTDs) Term assigned to identify a group of injuries that classically result from long-term and repeated “wear and tear” on the musculoskeletal system. CUMULATIVE indicates injuries that develop gradually over time, and result from many repeated stresses on a particular body part. TRAUMA signifies bodily insult or injury from mechanical stresses. DISORDERS describes the adverse health effects that arise from chronic exposure to repeated trauma. Ergonomics

Cumulative Trauma Disorders Your Job Your Body Trauma Healing Valve

Your Job Your Body Trauma Healing Valve CTD Cumulative Trauma Disorders

Workplace Applications Manual Materials Handling Cumulative Trauma Disorders (CTDs) Video Display Terminals (VDTs) Workplace/Workspace Design Control & Display Design Adverse Environmental Conditions Ergonomics

Win - Win Production Quality Compliance Compensation Costs Healthy Workforce Careers/Employment Safety Working Conditions Ergonomics

OSHAct 1970 "General Duty Clause" Section 5. (a) Each employer - (1) shall furnish to each of his employees employment and a place of employment which are free from recognized hazards that are causing or are likely to cause death or serious physical harm to his employees; DUTIES Ergonomics

Voluntary Guidelines o OSHA Meatpacking Guidelines o General Industry Guidelines (dropped in lieu of standard) o Food Distribution Warehouses o ANSI HFS-100/1988; VDTs o ANSI Z-365; Control of CTDs Ergonomics

Nature of Injury Strains/Sprains 43% CTDs 5% Occ Illness 4% Laceration/Puncture 11% Fractures 9% F.B. in Eye 3% Dislocations 2% Contusions 9% Burns 3% Amputations 1% 1990 Ohio Injury/Illness Claims Information Ergonomics

Part of Body Back 20% Face/Neck 3% Trunk/Internal 11% Arms 12% Hands 5% Fingers 11% Legs 13% Feet/Toes 5% Mult/Major 13% Other 15% Eyes 4% Head 2% 1990 Ohio Injury/Illness Claims Information Ergonomics

CTD Recognition Rising In 1990, 59% of all Occupational Illness Claims are logged as CTDs In 1990, 59% of all Occupational Illness Claims are logged as CTDs One half of all CTD claims are logged as Carpal Tunnel Syndrome (CTS) One half of all CTD claims are logged as Carpal Tunnel Syndrome (CTS) Ergonomics

Ohio Back Injury Claims In 1990, $513 M was paid out by the BWC for back injuries alone In 1990, $513 M was paid out by the BWC for back injuries alone Ergonomics

Average Total Claim Cost (Thousands) Direct Costs = Medical + Comp + Reserve Direct Costs = Medical + Comp + Reserve Indirect costs are estimated anywhere from 4 up to 20 times direct costs Indirect costs are estimated anywhere from 4 up to 20 times direct costs BWC data BWC data Ergonomics

Iceberg Analogy Accident Cost Medical Payments Compensation Supervisor time to investigate Breaking in substitute Efficiency due to break-up of crew Damaged tools/equipment Down-time Overhead $ while work disrupted Failure to meet deadline/fill orders Loss of production Loss of good will Overtime to make up production Hiring costs Lost time by fellow workers Direct Costs Indirect or Hidden Costs

Worksite Analysis Key Elements I.Records Analysis

Worksite Analysis Records Analyses help identify & prioritize jobs to evaluate. Accident ProductionPersonnelEmployer/Employee Records Records RecordsSurvey OSHA log 200Seasonal TrendsTurn-over RateSymptoms survey Incidence RateQuality ControlAbsenteeismEarly reporting mechanism Prevalence RateModel ChangesSuggestion award program First-aid logsBottlenecks Accident Invest. Workers’ Comp.

Worksite Analysis Key Elements I.Records Analysis II. Risk Factor Recognition

OCCUPATIONAL RISK FACTORS Attributes of a job or task that we know increase the probability of developing a musculoskeletal cumulative trauma disorder (CTD) FORCE (Internal & External) POSTURE REPETITION INSUFFICIENT REST Worksite Analysis

OCCUPATIONAL RISK FACTORS Attributes of a job or task that we know increase the probability of developing a musculoskeletal cumulative trauma disorder (CTD) FORCE (Internal & External) POSTURE REPETITION INSUFFICIENT REST Worksite Analysis

Synovial Sheaths Carpal Ligament (Extensor Retinaculum) Extensor Tendons

TWO KINDS OF BACK INJURIES MUSCULARSPINAL

RestingDynamicStatic blood flow needed blood flow supplied blood flow needed blood flow needed blood flow supplied blood flow supplied

Vertebrae Top View Side View

Micro-fractures in Vertebral Endplate Scar tissue from healing fractures hinders passage of nutrients to disc resulting in gradual weakening and de-generation.

Disc Degeneration

Hierarchy of Controls Ergonomics Engineering Controls Workstation Design Tool Design Process Modification Mechanical Assist Administrative Controls Training Job Rotation Pacing Policy Job Enlargement Personal Protective Equipment Gloves Wraps Shields FIRST CHOICE Second Choice Last & Least

BACK INJURIES

MAN VS. MACHINE DECISION MAKING LOW REPETITION ACTIVITIES LOW FORCE APPLICATION DELICATE FORCE APPLICATION TAKING INSTRUCTION HIGH REPETITION ACTIVITIES HIGH FORCE APPLICATION HAZARDOUS ENVIRONMENTS

STATURE EYE SHOULDER ELBOW HIP KNEE 21.67” 21.5” 19.3” 20.0” N.A. E. A. L.A. 36.0” 36.4” 32.7” 34.0” N.A. E. A. L.A. 43.5” 43.3” 40.8” 40.9” N.A. E. A. L.A. N.A. E. A. L.A. 69.1” 68.6” 65.2” 65.1” N.A. E. A. L.A. 64.6” 64.4” 60.7” 60.9” N.A. E. A. L.A. 56.7” 56.5” 52.8” 53.2” N.A.= NORTH AMERICA E.= EUROPE A.= ASIA L.A.= LATIN AMERICA 50th PERCENTILE MALE

D E C B A Horizontal Work Envelope A-Normal reach radius B-Sitting/Standing distance C-Extended reach radius D-Beginning work distance E-Optimum work area Max = 15” Max = 9” Max = 22” Ideal = 4” 10” x 10”

SIT OR STAND? Type of Task Lifting more than 11lbs Work below elbow height (e.g. packaging or assembly) Extended horizontal reaching Light assembly with repetitive movements Fine manipulation and precision tasks visual inspection and monitoring Frequent moving around First Choice Standing Sitting Sit-Standing Second Choice Sit-Standing Standing

A > 4” B = (for power grips) 1.5” C = 3” to 3.5” (for precision operations).45” Manual Tool Dimensions