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System Design:. Organizational and Social Aspects. Systems Ergonomics. Applying knowledge of ergonomics to the design of systems. Steps needed for an ergonomic approach: Formulation of goals. Analysis and allocation of function. Design concept. Detailed design.
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System Design: Organizational and Social Aspects
Systems Ergonomics Applying knowledge of ergonomics to the design of systems. • Steps needed for an ergonomic approach: • Formulation of goals. • Analysis and allocation of function. • Design concept. • Detailed design. • Realization, implementation and validation. • Evaluation.
Formulation of the System’s Goals Obviously, you need to know what the system you’re making needs to be capable of before you can design it. This step involves selecting specific requirements, but does not establish any methods to accomplishing the goals. Methods for deciding on specifications: • Unstructured and structured interviews. • Unobtrusive observation of existing systems. • Questionnaire surveys. • Market research. • Make stuff up – because nobody will notice anyway and you can blow the rest of your budget at the bar.
Analysis and Allocation of Function In identifying and describing functions to be performed, abstract terms (abstract functional thinking) may prove helpful in finding new methods, breaking through semantic barriers, and allowing for a wider range of components. After required functions have been identified, they are allocated between operators and machines. That is, the level of automation in the system is defined, generally into three catagories: • Functions that must be performed by machines. • Functions that must be performed by humans. • Functions that can be carried out by either or both together.
Design Concept At this point, the specifications and function allocations are put together into a design concept, using methods of concept generation (like value engineering) or through simple brainstorming. Although merely a concept, it should be detailed enough to describe the work system’s structure and the interactions between components of the system. Functions allocated to workers are sorted into tasks, roles, and jobs.
Detailed Design Human and machine components are developed in parallel to save development time. Ergonomics should act as a link between the two. This stage should include the design of work organization, work tasks, jobs, work environment, work equipment (along with work hardware and software), and workspaces and workstations.
Realization, Implementation, and Validation Realization – Procurement and installation of the new system on site. Implementation – Management and changeover from the old system, including training of operators. Validation – Observing that the system is functioning in a way to meet the requirements.
Evaluation Seeks to determine how well the system meets identified requirements. Quality Control – A system is said to be of good quality if it meets the set requirements. Quality control should be monitored during the design stages to ensure that nothing is designed against ergonomic standards.
Organizational Aspects Sociotechnical systems theory • Linking of technical and social subsystems through the use of work organization. • Table 16.2 – Principles of sociotechnical job design. 1. Compatibility 2. Minimal critical specification 3. The sociotechnical criterion 4. The multifunction principle 5. Boundary location 6. Information flow 7. Support congruence 8. Design and human values 9. Incompletion
OSHA (the Occupational Safety and Health Administration) Monitors about 6 million workplaces and 93 million workers. Has attempted to establish workplace standards in response to the growing number of musculoskeletal injuries that are being filed for compensation by injured workers. Aims to “prevent, eliminate and reduce ergonomic hazards in the workplace.” General guidelines for most industries, and specific ones for “high-risk” industries (i.e. construction). Worksite analysis plays a large role in adjusting tasks to be more ergonomic (best repeated annually with high-risk jobs). Table 16.3 – Key features of OSHA’s program guidelines for meatpacking plants.
Legislation in the European Union Directives require each state to introduce legislation that covers: • Management of health and safety • Manual handling of loads • Work with display screen equipment (VDUs) • Use of personal protective equipment • Use of work equipment • Workplace design (health, safety and welfare) Responsibility of worker’s health is placed on the employer, who is required to carry out risk assessments, monitor employee health, and make sure workers are suited for their jobs (in competence, training, and with proper equipments for health and safety).
Dwyer and Raftery • Provided further evidence for the need of a systems approach that considers ergonomics by investigating industrial accidents. • Organizational factors that are related to accident frequency • Working on a piece rate basis • Under-nutrition of employees • Extended work hours • Absence of integration between different work groups
Incentive schemes • Use of positive reinforcement rather than negative. • Incentives can be of many different forms • Cash bonuses • Points or stamps that can be traded in for fun new stuff!! • Employee of the Month awards These schemes show gains for the short term.
Implementing new technology New technologies take time to mature. New technologies can introduce secondary tasks which negate their benefits. Productivity paradoxes Quality Lack of technology Time lags Inappropriate expectations Computerization of administrative functions can end up costing more to maintain.
Disadvantages of IT • Waiting for programs to run or for help to arrive. • Double checking printouts for accuracy. • Rearranging files. • Games. • Internet – not just because of browsing, but when systems are used over it, there is more wait. • Overemphasis on quality. • Employees having to cope with new, more complex systems. • User attention becomes focused on software.
Organizational braking factors on IT productivity – Hopwood says decision makers use cost-benefit analysis, and often weigh cost much more heavily. • Incremental alternatives – The use of ‘Information Appliances’ that help people carry out specific functions may be a better way to get IT into the workplace. • Containerization – Greatly reduced shipping costs by loading the trucks on the boat and eliminating dock workers. Macroergonomic interventions bring improvements by redesign of organization, rather than user interfaces and workspaces. • Trading patterns – International trade has changed from low-value goods to high-value added goods.
Shiftwork • Productivity has a natural rise and fall as the work day progresses because of psychological cues (such as lunch time getting closer, etc). • Shiftwork can be very complicated to completely implement because of social issues, and incomplete adaptation can result in increases of employee absense. • Considerations when designing shift systems include identifying employees who might prefer night work to reduce the need for adaptation.
Adaptation of a new shift system must take place over at least a week. • Where possible, minimize changes in work hours. • Three-shift system may be the best compromise if voluntary night workers can’t be found. • Permanent night shifts with rotating day shifts is the best option. • Shift designers must take into account social settings such as night workers not having methods of transportation. • 8 hour shifts are preferable, but some jobs may be better suited to 12 hour shifts.
Psychosocial factors • Much of the emphasis of ergonomics is on human capabilities and limitations, but other matters may require consideration as well. • Motivation – higher-level needs should not come into play until lower-level needs are met. • Job enlargement – gives operator more tasks to reduce risk of repetitive injuries. • Job enrichment – extend workers duties vertically, such as making them responsible for quality control as well. May result in workers wanting increased pay. • Job satisfaction – Hygiene factors (Table 16.4), Table 16.5 – how to improve job design. Both are based on Hertzberg’s proposed principles on job satisfaction.
Psychosocial factors cont’d These factors can be used to mediate the prevalence of disorders or behaviors associated with the disorders. Table 16.6 summarizes psychosocial risk factors for back and neck pain (as found by Lindon) In designing experiments and field trials, subject reactivity, or changes in behavior brought about by being in an experiment, must be accounted for and dealt with. Novel interventions, such as new office furniture, work because they’re novel, but are not long-term fixes. Placebo effects are very common.
Litigation • In cases where there is a real injury and it may be work related, ergonomists are brought in to determine: • Whether there were risk factors in the environment • Whether the employer could reasonable have known about them • Whether the employer was negligent in not taking all reasonable steps to safeguard the employee’s health.
Cross-cultural Considerations • Cognitive structures differ between cultures. That’s not to say any are better than others, but this must be considered when bringing new technologies to other cultures. • Having an understanding of cultural and religious beliefs can be used in designing workplace slogans and propaganda.
Effectiveness and Cost-effectiveness • Three approaches to cost-effective ergonomic interventions: • Identify high risk areas. Even expensive interventions can be cost-effective if they reduce risk. • Identify problems that are extremely common and implement common interventions. • Design new systems that work by using people and technology more effectively that are designed with ergonomics in mind. It must be kept in mind that arguments for cost-saving must specify how ergonomics will save money, rather than just passing it off by saying “The solutions will pay for themselves.”
