MODULE: INTRODUCTION TO ERGONOMICS

THE PROCESS OF ERGONOMIC WORKPLACE RISK ASSESSMENT (Continued):

STEP 5: Prevention and control of ergonomic risk factors

Ergonomic risk factors are prevented primarily by effective design of the workstation, tools and job. The employer must determine all measures necessary to eliminating or reducing the hazards identified in the work site analysis by changing the jobs, workstations or environment to fit the worker. It is an active process of reducing the risk of injury by changing the things that contribute to the risk factors.

Risks can be reduced through use of the following types of controls:

• Engineering controls: these controls are the most effective as they make permanent changes that eliminate or reduce the hazards at the source. They involve making changes to workstations, tools or equipment to avoid work-related musculoskeletal hazards. Engineering control strategies include the following factors:

  • Workstation, equipment, tool or work process redesigns e.g. sequence of assembly. Workstations should be design for a specific task and be easily adjustable with sufficient workspace.
  • Use of mechanical assist devices to reduce manual handling
  • Change in the process or product to reduce worker exposure to risk factors. (For example, reduction of flashing by improved fit pf plastic moulds).
  • Modifying containers/parts presentation e.g. height adjustable material bins.
  • Changing workstation layout, for example height-adjustable workbenches or locating tools and materials within short reach distances.
  • Change the way parts, tools, and materials are to be manipulated, such as the use of vices/jigs to hold work pieces or suspended tools.
  • Tool and handle designs: the appropriate tool should be used for the task and tools should be available in a variety of sizes to achieve a proper fit
  • Change in materials, for example, light-weight packaging materials to reduce lifting loads
  • Work methods should be designed to reduce repetitive motion, excessive force or poor posture. Examples of this are: changing assembly access and sequence.

  For illustrations of some basic ways for controlling ergonomic risk factors, see Figure 2: page 33 of the NIOSH, Elements of ergonomics programmes

• Administrative or work practice controls to reduce exposure to ergonomic risk factors including scheduling more rest breaks, rotation of jobs, reduction in shift length, adjusting work pace, broadening job content, regular maintenance programme, effective housekeeping, training workers to recognize and reduce exposure to ergonomic risk factors, reduction in work pace and instruction in safe and proper work practices.

  Proper work techniques should include appropriate training and practice time, correct lifting techniques, proper use and maintenance of hand/power tools and correct use of ergonomically designed workstations.

  Monitoring should include a periodic review of techniques and practices and their effectiveness.

  Administrative controls are only helpful as temporary measures as they do not eliminate hazards.

• Implementing Controls consists of:

  • trials of the selected solutions, testing that solutions actually work.
  • modifications or changes that may be needed
  • full-scale implementation.
  • periodic evaluation of control effectiveness to ensure that the controls reduced or eliminated the ergonomic risk factors and that new risks have not been introduced.
  
  

• Evaluating of control effectiveness by using the following indicators:

  • Reduction in the incidence rate of WMSDs.
  • Reduction in the severity rate of WMSDs.
  • Increase in productivity and quality.
  • Reduction in absenteeism.

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