A Total Ergonomic Design Approach to Enhance the Productivity in a Complicated Control System

METHODS

To achieve the above objective a hierarchical approach based on several distinct techniques is employed. The prescribed algorithm is based on a set of well defined, hierarchical steps in order to develop a total ergonomic design model for a specific system being studied. These steps are accomplished in three discrete phases which are Identifying the system, Analyzing the results and Designing (Developing) a new system. In fact, any attempt for designing or optimizing a system, have to be started with identification. This step can be passed by data gathering techniques, successfully. Then after checking the validity of results, the designer must analyze the gathered information to find out the deficiencies of the under studying system and finally the suggested system must be prepared (Bailey, 1989; Eastman Kodak Co., 1983; 1986).

In identifying phase all procedures, processes, components and operations of the system under study must be fully comprehended. Some techniques are employed for this reason that we are trying to explain them in the following:

Observation method: For conducting this method, objectives of the investigation must be settled, first. In fact understanding the problem and the objectives of the survey is a really important matter. Respecting to the objectives, some notes will be pointed out and consequently some checklists will be developed for leading the directions of observation and also the other methods. These checklists will clear the total ergonomic concepts that must be observed during research and can be used as a guideline for investigating the total ergonomic factors.

Interview method: An effective and practical integrated ergonomic and macroergonomic model should be designed for the real people in the loop, namely, operators, supervisors and managers. Therefore, managers and operators are required to be interviewed to reflect their opinion about the working condition and ergonomics considerations. This technique should cover the issues related to: safety, teamwork, anthropometric measures, management factors, relationships, documentation, standards, training and etc. The results of interviewing method would enable us to develop a total human factors and anthropometric questionnaire discussed in the following as another method for data gathering.

Task and method study: This technique is to study all rules and procedures that construct work and information system relationships. For this reason all the components should carefully studied and the existing methods of working, required to be revised. In this method, all the sub systems must be surveyed according to documentation, existing rules and procedures and organizational responsibilities and information relationships. Task descriptions also, should be found out in this step. Our experiences reveal that flowcharts and relationship diagrams are ideal tools to apprehend the operations and processes of the studying system. Moreover, a detailed flowchart and a schematic diagram could help us locate weak points and critical areas.

Questionnaires: A detailed questionnaire must be designed and presented to operators by referring to the findings of the interview technique and utilization of human factors, safety and organizational standards. The inquisition process must contain valuable and practical information related to human, safety, management and organizational factors In addition; several questions in regard to teamwork and training must be developed.

Anthropometric survey: At this stage, a detailed anthropometric questionnaire is developed and presented to all operators. The questions must be designed by referring to the results of interview technique and employment of anthropometric and ergonomics standards. The survey may contain information about working postures, height, weight, seating position, standing position, noise, light, pollution and etc. In addition the anthropometrical factors must be measured carefully, by using the ergonomic measurement devices. The critical factors in relation to working condition must be introduced. For instance, a high percentage of the operators claiming moderate to high pain or tiredness in their hands could be indicative of improper height of workstations or unsuitable instruments and etc.

In evaluation phase, all the diverse data which have been gathered by foretelling techniques, categorized in special tables and diagrams and will be analyzed by researcher in order to prepare the diagnostic micro and macro ergonomic system. It must be noted that each system is atypical and the problem solving approach of each system must be based on systems uniqueness philosophy. This means each project is unique and requires an approach that dwells on its own contextual requirements. Thus the methodologies required to achieve an integrated ergonomics and macroergonomics program so a total ergonomic approach should be employed and an integrated concept must be considered.

The analysis techniques are more various than the identification’ methods, but we divide them into two main categories: quantitative and qualitative methods. In fact all the mathematical based technique which use the statistical aspects and methods or measuring techniques for anthropometric design and layout development may be considered as quantitative methods. The results of much identification’ surveys may be analyzed by quantitative methods such as statistical hypothesis tests, pie charts, bar charts, t-test, correlation analysis and analysis of variance. The results of this study must stress weak and strong points in regard to the above factors.

Moreover, anthropometric measures should be checked against standards in each single workstation. Measures are related to operators, workstations, instruments and work environment. They are categorized as: height, width, length, reach, noise, humidity, temperature, pollution, illumination, light and weight. An anthropometric measurement is a complementary analysis technique to anthropometrics survey explained in the pervious section. The results should help us locate stationary human factor deficiencies and safety and environmental issues.

Finally a complete qualitative analysis is conducted to uncover hidden points in relation to safety and ergonomics issues. This step acts as a final check against macroergonomics factors discussed before. The analysis of macroergonomics factors often needs qualitative analysis as well as some of complicated ergonomics factors. The lack of standards and have not any numeric method in most of macroergonomic aspects, causes this matter and approve the necessity of using qualitative analysis. In this method first, all pervious findings are reviewed to expose hidden macroergonomics issues such as managerial or training problems. Second, the studying system must be carefully visited to unveil hidden issues. Totally the results of discussed methodologies would highlight major deficiencies and enable us to implement an integrated ergonomics and macroergonomics in the supposed system.

Fig. 1:	The general steps required achieving total ergonomic design program

In developing phase the results of two discussed phases, must be understood carefully in order to prepare a practical suggestion that can be used as a diagnose for decreasing the deficiencies and increasing the efficiency, all over the studying system. Considering the obtained results of analyzing phase, researcher should develop a new model for designing: interfaces, work environment, work stations, organizational structure and behavior, methods of relations, communication directions, teamwork and etc. This model must be based on ergonomics standards and managerial concepts. Implementing a total system design or developing a diagnostic suggestion can be the real output of such studies. Our experiences indicate that using this algorithm; can be successful for increasing the productivity of the whole system outputs.

Fig. 2:	The cycle of total ergonomic design program as an optimizing method

Figure 1 and 2 are to presents a schematic diagram for introducing this total system approach as a flowchart and the optimized cycle of total ergonomic design program.

RESULTS AND DISCUSSION

One of the great thermal power plants in Iran was considered as the case of our study. The managers were familiarized with the benefits of utilizing a total ergonomic approach to enhance the productivity at the power plant during a short seminar. The objectives of this investigation were defined as improvement of working conditions, reduction of lost workdays as the result of injuries, utilization of proper operating procedures for operators and reduction of plant’ trips statistics during the year.

Identifying phase: Maintenance shops and control rooms were selected and all operators and supervisors, also the managers were involved in our study. The hierarchical algorithm prescribed in this paper was applied to the power plant. For the successful implementation of macroergonomics program, the rules and procedures, operations and processes, relationships and communications were carefully studied. A detailed flowchart and a schematic diagram were developed. The questionnaires were designed and presented to all operators. Also a complete anthropometric study was conducted. All the gathered data were analyzed, by respect to ergonomic standards and macroergonomic rules. The statistical analysis, comparing to standards and organizational studies, were conducted as analyzing methods.

Evaluation phase: The results show numerous problems in regard to microergonomics and macroergonomics conditions. Poor workstation and job design, not efficient interfaces, lack of training and teamwork, lack of well defined rules and procedures, lack of job descriptions, not enough light and dangerous situations for working are the most important findings of this research. The results of questionnaires also were as useful as an analyzing device. All the results evaluated as an independent statistics’ variable and also they investigated in meaningful pairs of dependent statistics’ variables by using analysis of variance method. The statistics’ analysis results were compared with existing standards and the differences were marked for more evaluations.

Developing phase: Then as a solution we design a total ergonomic system based on the existing system of power plant. All the procedures documented in accordance with ISO 9000 series standards of quality assurance, the descriptions of each one defined, the ergonomic conditions improved and a training plan prepared. The plant is at the stage of implementing our system for improving productivity and reliability.

CONCLUSIONS

It should be noted that the traditional ergonomics techniques would not have been able to locate all of the preceding problems. The distinguished aspect of this study is the employment of a total system approach based on integration of the traditional human factors as well as macroergonomics factors. To conduct an integrated ergonomic study, we must consider the whole and avoid the trap of dealing with specialties with which we feel comfortable in conducting such a study. Such a program requires teamwork between operators, supervisors and managers. The hierarchical technique should be cautiously implemented to avoid local or short-term improvements. This requires a team of experts specializing in human factors, organizational design and statistics.

Moreover, the experts should familiarize with the concept of macroergonomy. It should be noted that each system is unique and the problem solving approach of each system must be based on systems uniqueness philosophy. In order to create an intellectual interface between operators, machines and management, the following steps are suggested:

Peter Drucker states that the emerging theory of manufacturing will require that every manager be responsible for integrating people, machines and time (Drucker, 1990). The managers need to adopt a more systemic approach understanding the complex interrelationships in the system. Systemic understanding is difficult to achieve, but is necessary if we are to face with increasing uncertainties and competitions of manufacturing systems in the twenty first century.

FURTHER RESEARCH DIRECTIONS

We have developed an integrated approach to study ergonomics and macrogramics issues to complicated control systems. This approach is applied in a large power plant and the results have been presented. The approach that developed here is useful for further ergonomics an macroergonomics studies. Now a days organizational aspects of information technology and information systems (IT, IS) play vital role in macroergonomics studies. Infact, in any macroergonomics study regardless of theoretical or practical must consider IT, IS aspects of organization (Boyer et al., 1997; Brynjolfsson and Hitt, 2000; Hitt and Brynjoflsson, 1996). Specifically, advanced digital control equipments are introduced and utilized in control rooms. Advanced technologies need new organizational infrastructure, which could be considered in a macroergonomics study since it looks at the whole organizational infrastructures. We therefore propose to study the macroergonomics aspects of IT,IS as the future application of the approach discussed in this study.