MODULE: INTRODUCTION TO ERGONOMICS

Critical design factors to be considered:

• Anthropometric principles:

  Anthropometry means measurement of humans. Difference in statue is important in the design of equipment and work environment and has implications for the way most products and devices are designed. Body size and proportion vary greatly between different populations. Anthropometric data can provide the designer with guidelines for dimensioning workspaces and a perspective on usability issues so that "little people can reach and the big person has enough room"!

• Biomechanics: This is the application of the principles of mechanics to the study of biological systems dealing with the mechanical aspects of body movement.
• Human sensors such as vision and hearing.
• Psychological system; psychological stress can result in fatigue and reduced motivation possibly leading to accidents/illness
• The physiological system is effected by environmental stressors such as heat, noise and vibration.

Treating the risks/reporting to management:

All the steps taken during the risk assessment must be systematically recorded. An action plan must be developed and implemented, focusing first on the most significant risks, showing clear motivation for recommendations and decisions taken. The process should be kept simple, realistic and practical with the use of descriptive techniques rather than statistical techniques. Recommended action converts the risk analysis into actions to reduce risk. Recommended options are evaluated in terms of viability, cost and benefits with the aim of choosing the most suitable and practical way of reducing risk to a reasonable level.

Cost justification:

• Labour turnover - recruitment costs.
• Development costs - training costs.
• Skill enhancement costs.
• Separation costs - severance pay, vacant position.
• Absenteeism costs - compensation costs, medical costs, replacement costs.
• Productivity costs - slow work rates, wastage.

Versus

• Investment capital needed to implement ergonomic interventions.
• Determine the reduction in costs due to these interventions.

Ergonomics must be economically justified. Justify ergonomics based on the payback period - preferably within a period of 2 years or less.

Tertiary prevention:

If prevention and management have failed and the injuries become chronic, then chronic injury intervention should begin with a goal to ensure return to work without further complications and to prevent disability. If the injury is too severe to allow return to work then it is important to work towards claim resolution and if possible, to return the employee to a job that meets his/her reduced capacity. Re-evaluation of injured employee should be done by everyone involved in the treatment to minimize confusion and ensure that all barriers to return to work are discussed.

A rehabilitation program should use a multidisciplinary team consisting of:

• independent medical examination.
• functional/physical capacities evaluation.
• vocational rehabilitation assessment.
• psychological evaluation.
• work-hardening program.
• pain clinic program.

Ergonomics for the Prevention of Musculoskeletal disorder:

• Guidelines for Retail Grocery Stores.
• Guidelines for nursing homes.
• Farming ergonomic booklet NIOSH*.
• Grocery Warehousing etool - Packaging.
• Grocery Warehousing etool - Storage.

* US government - public domain

OSHA - Meat packing assessment is a good example of an in-depth ergonomic assessment.

List of other ergonomic sites of interest:
www.cdc.gov/niosh/topics/ergonomics/
http://keats.admin.virginia.edu/ergo/home.html

General Introduction to Occupational Health: Occupational Hygiene, Epidemiology & Biostatistics by Prof Jonny Myers is licensed under a Creative Commons Attribution-Noncommercial-Share Alike 2.5 South Africa License