INAR 122

1. INAR 122 HUMAN FACTORS

2. DEFINITION: ERGONOMICS IS THE SCIENTIFIC STUDY OF THE RELATIONSHIP BETWEEN MAN AND HIS WORKING ENVIRONMENT. ERGONOMICS

3. HISTORY OF ERGONOMICS • The foundations of the science of ergonomics appear to have been laid within the context of the culture of Ancient Greece. • Evidence indicates that Hellenic civilization in the 5th century BC used ergonomic principles in the design of their tools, jobs, and workplaces.

4. HISTORY OF ERGONOMICS • World War IImarked the development of new and complex machines and weaponry, and these made new demands on operators' cognition. • The decision-making, attention, situational awareness and hand-eye coordination of the machine's operator became key in the success or failure of a task. • It was observed that a fully functional aircraft, flown by the best-trained pilots, still crashed. • In 1943, Alphonse Chapanis, a lieutenant in the U.S. Army, showed that this so-called "pilot error" could be greatly reduced when more logical and differentiable controls replaced confusing designs in airplane cockpits.

5. HISTORICAL BACKGROUND: IN 1949 A GROUP OF PEOPLE DECIDED TO FORM A SOCIETY FOR ‘THE STUDY OF HUMAN BEINGS IN THEIR WORKING ENVIRONMENT’ ERGONOMICS / HUMAN FACTORS ERGO + NOMOS WORKS THE NATURAL LAWS ERGONOMICS

6. HUMAN FACTORS: • HUMAN FACTORS IS THE PRACTICE OF DESIGNING ARTIFACTS SO THAT THE USER CAN: • PERFORM, • USE and, • OPERATE SERVICES AND SUPPORTIVE TASKS WITH MINIMUM STRESS and MAXIMUM EFFICIENCY

7. STUDY OF HUMAN BEINGS IN THEIR WORKING ENVIRONMENT ERGONOMICS INVOLVES: MAN-MACHINE MAN-ARTIFACT ERGONOMICS RELATIONSHIP

8. ARTIFACT: ANYTHING SUCH AS A PRODUCT OR SPACE THAT IS DESIGNED FOR HUMAN BEINGS.

10. GENERAL ENVIRONMENT INCLUDES VARIABLES SUCH AS: LIGHT,NOISE, DUST, FUMES, ETC.

11. IMMEDIATE ENVIRONMENT INCLUDES VARIABLES SUCH AS: DIMENSIONAL, POSTURAL, AND MECHANICAL PROBLEMS

12. VARIABLES OF MANKIND • AGE • SEX • EDUCATION • TRAINING • EXPERIENCE • PSYCHOLOGY • NUTRITION

13. BASIC SCIENCES INVOLVED IN HUMAN FACTORS • The basic human sciences involved are anatomy, physiology and psychology. • These sciences are applied by the ergonomist towards two main objectives: • the most productive use of human capabilities and, • the maintenance of human health and well-being.

14. DISCIPLINES THAT CONTRIBUTE TO HUMAN FACTORS: • ANATOMY:IS BASICALLY THE STUDY OF THE STRUCTURE OF THE HUMAN BODY. • IT IS IMPORTANT BECAUSE WE DESIGN FOR VARIOUS CRITERIA DEMANDED BY THE HUMAN BODY • The contribution of anatomy lies in improving physical ‘fit’ between people and the things they use, ranging from hand tools to aircraft cockpit design.

15. DISCIPLINES THAT CONTRIBUTE TO HUMAN FACTORS: • PHYSIOLOGY: GIVES INFORMATION ABOUT THE FUNCTIONING OF THE HUMAN BODY. • a) Work physiology addresses the energy requirements of the body and sets standards for acceptable physical workrate and workload, and for nutrition requirements. • b) Environmental physiology analyses the impact of physical working conditions – thermal, noise and vibration, and lighting – and sets the optimum requirements for these.

16. DISCIPLINES THAT CONTRIBUTE TO HUMAN FACTORS: • PSYCHOLOGY: Psychology is concerned with human information processing and decision-making capabilities. • In simple terms, it is the cognitive ‘fit’ between people and the things they use. Relevant topics are: perception, long and short-term memory, decision-making and action.

17. DISCIPLINES THAT CONTRIBUTE TO HUMAN FACTORS: • a)Physiological Psychology: Deals with the functioning of the brain and the nervous system. eg. When a sound or smell comes from the environment, the brain reacts and a decision is made. • b) Experimental Psychology: Deals with the parameters of human behaviour.

18. MANAGMENT: Deals with the organization of the work and the work space. eg. Where you should put the things in a kitchen or in an office. DISCIPLINES THAT CONTRIBUTE TO HUMAN FACTORS:

19. DISCIPLINES THAT CONTRIBUTE TO HUMAN FACTORS: • ENGINEERING:Gives information about the environment the human is within. This is important because, for example, the temperature or the amount of humidity in a room has to be known to obtain human comfort.

20. DISCIPLINES THAT CONTRIBUTE TO HUMAN FACTORS: • DESIGN: Is the way of representation of any artifact. • When we design any artifact we must consider human health, safety, and comfort. We use ergonomic principles to do this.

21. In a phrase, • “the job must ‘fit the person’ in all respects, and the work situation should not compromise human capabilities and limitations”. Ergonomics deals with the interaction of technological and work situations with the human being.

22. Effective Use of Ergonomic Principles Improves: • Productivity, • Morale and, • Stress Reduction

23. QUESTIONS • 1. WHAT IS ERGONOMICS • 2. WHAT ARE THE VARIABLES OF MANKIND? • 3. WHAT ARE THE DISCIPLINES THAT CONTRIBUTE TO ERGONOMICS?

24. ANTHROPOMETRICS • Achieving good physical fit cannot accept one mean feature when one considers the range in human body sizes across the population. • The science of anthropometrics provides data on dimensions of the human body in various postures. • Biomechanics considers the operation of the muscles and limbs, and ensures that working postures are beneficial, and that excessive forces are avoided.