Edwin Tytyk

Heuristics in Ergonomic Design of Portable Control Devices for the Elderly

The prolonging life expectancy and, as a result of it, the growing number of people of elderly age means that more attention should be devoted to the design of ergonomic equipment which includes the needs of this group of customers. Elderly people often suffer due to poorly designed technical facilities, which discourages them from using equipment to improve the quality of their lives. The article summarizes the identified needs of elderly people in relation to control devices along with the general guidelines for the ergonomic design and design approaches for people with disabilities including: universal design, inclusive design, design-for-all, barrier-free design, and accessible design. Among the most important limitations of elderly people are included: reduced psychomotor and sensory efficiency and range of motion, decreased strength, and a decreased ability to remember. In this way a checklist is comprised of criteria such as anthropometric compatibility, ease of use and handling, transparency and visibility, tolerance for error, sensory substitution, and palpability and feelings. The list of identified criteria is evaluated by users resulting in a quantification of individual requirements. Based on interviews with users, an identification and classification is also made of the basic groups of control devices used by the elderly. As a result of these measures checklists are obtained to evaluate each group of the control devices, which examine the typical and commonly used devices in the Polish market. Some selected devices have also been subjected to an evaluation during arranged performance situations involving elderly persons. The information obtained during this is discussed within the article.

Human error and response to alarms in process safety

Human operators are required to respond to alarms in normal conditions, and also to find solutions to unexpected situations in real time. The aim of this study is to increase the knowledge of human responses to alarms in the context of occupational situations. It describes how humans contribute to accidents, and pays special attention to the assurance of process safety assurance, which is in part realized by timely reactions to system alarms. An experiment involving an operator´s reaction times to alarm signals was undertaken to investigate whether there are differential responses to visual as opposed to auditory alarms. The findings in the research show that visual alarm indicators are perceived faster than auditory signals. Furthermore, there was a significant negative correlation between the number of errors and reaction time, indicating an individual difference in error-proneness when reacting to visual alarms in a supervisory task.Human operators are required to respond to alarms in normal conditions, and also to find solutions to unexpected situations in real time. The aim of this study is to increase the knowledge of human responses to alarms in the context of occupational situations. It describes how humans contribute to accidents, and pays special attention to the assurance of process safety assurance, which is in part realized by timely reactions to system alarms. An experiment involving an operator´s reaction times to alarm signals was undertaken to investigate whether there are differential responses to visual as opposed to auditory alarms. The findings in the research show that visual alarm indicators are perceived faster than auditory signals. Furthermore, there was a significant negative correlation between the number of errors and reaction time, indicating an individual difference in error-proneness when reacting to visual alarms in a supervisory task.

Ergonomic Implications of Technological Innovations in the Development of Computer Workstations

Relentless technological progress creates change in the work environment, including that of commonly used computer workstations. Determinants of change in this respect are both the changes in information and communication technologies as well as the more often exhibited concern for the welfare of employees. Technological innovations derive from a multifaceted improvement of a specified element of the technical environment (e.g., contrast, energy consumption for the next generation of computer screens), with the assumption that they will bring a benefit in terms of ergonomic quality of working conditions. Technological innovations can, however, cause a deterioration of identified in advance or often unknown parameters of the working environment, in particular, they can have negative consequences for ergonomic working conditions. The analysis found that technological changes satisfactory from the point of view of ergonomics.