Eduardo J Salazar-Vega MHP CPH. Ergo = work Nomos = laws It is an applied scientific/engineering discipline concerned with the interaction among.

ErgonomicsEduardo J Salazar-Vega MHP CPH

What is ergonomics

Ergo = work Nomos = laws It is an applied scientific/engineering discipline

concerned with the interaction among systems and the people who operate and maintain them

OSHA defines it as “the study of the design of requirements of work in relation to the physical and physiological capabilities and limitations of people

Whenever a human becomes part of the operation of a system,

ergonomics become a necessary consideration

What is ergonomics?

Ergonomics

Physiology

Medicine

AnthropometricsBehavioral Science

Engineering

Other Considerations

Psychological factors –attitude, motivation

Somatic factors –age, sex, health, size

Physiological factors –fuel, oxygenLearning factors –training,

knowledge, adaptabilityNature of work –intensity, duration,

rhythm, technique, positionEnvironment –heat, cold, noise,

altitude, pollution

Approaches

Reactive ergonomics –corrective actions after the event occurs

Proactive ergonomics –corrective actions taken before injuries and illnesses occur

Problems to solve

Tool/product designWorkplace Design Integration of new technologyEnvironmental ConditionsMaterials handlingTask/job designWorkstation design

The goal of ergonomics is to make the workplace as adaptable as possible to the

people who will be working on it.

Common ergonomic issues - Workstations

Control and display design

Location and orientation of work surfaces

Posture/work height and reaches

Movements/repetitions Vibrations Accessibility Labels and location

aids Guarding and warnings Hand tools Machinery and

equipment design Size and shape of work

objects Weight of work

equipment and objects

Common ergonomic issues - Environmental

Lighting/noiseTemperature/humidityHousekeepingHazardous materials

Role/benefits of ergonomicsBenefits Manufacturing Measures

Increased operator acceptance • Injury/illness frequency and associated costs

• Worker’s compensation• Employee turnover• Employee absenteeism• Safety awareness

Increased dependability or reliability

• Scrap (error) rate• Maintenance costs• Machine up-time• Logistic support• Safety awareness

Flexibility and adaptability to change

• Reprogramming time/cost• Modifiability• Part change• Safety awareness

Increased efficiency and productivity

• Parts/hours (shift)• Scrap (error) rate• Safety awareness

Identifying ergonomics problems

Trends in accidents and injuries

Incidence of cumulative trauma disorders

Absenteeism, high turnover rate

Employee complaints Employee-generated

changes in the workplace

Incentive pay systems

Excessive overtime and increased work rate

Poor product quality Manual materials

handling and repetitive motion tasks

Improperly designed workstations for disabled people

Risk factors while manual material handling tasks

Job Weight Location Frequency/Duration Stability Grip Workplace geometry Environment

Personal Sex Strength Age Fitness Anthropometry Lifting

techniques and training

Data Collection

General observationsQuestionnaires InterviewsVideo analysisPhotographyDrawing or sketchingEvaluation of workers capabilitiesMeasurement of various risk factors

General Observations – Repetitive Trauma Disorders

Awkward postures

High task repetition

High force required

Mechanical stress points

Cold

temperaturesFit of work

glovesPoor

workstation design

Hand tool fitVibration

sources

General Observations – Manual Materials Handling

Lifting from the floor Lifting while twisting Lifting heavy weights Lifting bulky objects Lifting repeatedly Lifting above

shoulder height Lifting heavy items

while seated Pushing or pulling

loads

Nature of hand holds Storage methods Parts staging Floor condition in the

work environment Workstation layout Conflicting

movements Poor posture Bending

NIOSH Lifting Equations

http://www.cdc.gov/niosh/docs/94-110/

NIOSH Lifting Equations (cont)Horizontal Distance (H)Vertical Distance (V)Vertical Travel Distance (D)Frequency of Task (F)Duration of TaskAssymetry (A)Coupling (C)Weight of Load (L)

NIOSH Lifting Equations (cont)

NIOSH Lifting Equations (cont)

Recommended Weight LimitRWL = LC x HM x VM x DM x AM x FM

x CM

Lifting IndexLI = L/RWL

REBA/RULA

RULA: Rapid Upper Limb Assessment(McAtamney & Corlett, 1993)

REBA: Rapid Entire Body Assessment (Hignett & McAtamney, 2000)

Thank you!