The two final decades of the 20th century saw a significant increase in ergonomics activity (and resulting publications) in industrially developing countries (IDCs). However, a few ergonomics papers from Singapore, for example, were published in 1969 and 1970. This paper reviews developments in ergonomics in industrially developing countries from 1969 relying heavily on published papers although their quality varies considerably. Some criticism of these papers is offered. Most were concerned with the use of work tools, workstation operations, material handling and working environments especially in tropical climates. The similar problems encountered in a variety of countries are discussed, and the importance of low-cost solutions stressed. This study presents an overview of ergonomics research in IDCs. It concentrates on ASEAN countries whilst recognising the valuable work done in other areas.

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Using physiological and psychological measurements, we carried out experiments to investigate the influence of viewing distance and TV screen size on visual fatigue and feeling of involvement using 17-inch, 42-inch and 65-inch displays. The experiment was an ordinary viewing test with the content similar to everyday TV programs for one hour including scenery, sport, drama, etc., with commercials sandwiched in between. The number of participants was 16 (8 persons aged 21-31, and 8 persons aged 50-70) for each display size. In all, 48 participants viewed 3 display sizes. In our physiological evaluation, CFF (critical flicker fusion frequency), blink rate and a sympathetic nerve activity index were used; and in the psychological evaluation, questionnaires and interviews were employed. Our results, based on physiological and psychological measurements, suggest the optimum viewing distance to be around 165-220 cm, irrespective of screen size. Our evaluations, which are based on optimum viewing distance for minimal visual fatigue and a closer feeling of involvement, might therefore not agree with the currently recommended viewing distance, which is defined as 2 or 3 times the display’s height.

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The figpurpose of this study was to investigate the evaluation of differences in morphological qualities in physical strength of South Korean junior high school boys. The subjects were 201 first-year junior high school boys 13.6 ± 0.3years, 59.0 ± 12.8kg, 163.1 ± 7.4cm, in whom height, weight, BMI, fat mass, body fat percentage and soft lean mass were measured. Items of physical strength measured were the sit and reach, 20-m shuttle run, push-ups, and sit-ups. Morphological quality was judged from two aspects, a BMI evaluation of obesity or leanness and an evaluation of the level of fat accumulation derived from regression polynomials of body fat percentage against BMI. The subjects were classified into 9 groups according to differences in morphological quality. Of the physical measurement items, boys with underdevelopment of fat in the BMI slim and normal groups showed superior results in the 20-m shuttle run, push-ups and sit-ups. In contrast, boys with overdevelopment of fat in the BMI fatty group showed significantly poorer results in these items. Meanwhile, boys with underdevelopment of fat in the BMI fatty group showed a level comparable to boys in the BMI normal and excessive fat groups in the 20-m shuttle run; boys with normal and excessive fat in the BMI normal group and boys with excessive fat in the BMI slim group in push-ups; and boys with underdevelopment of fat in the BMI slim group in sit-ups. Performance in these measurements was evaluated in detail for boys with different morphological qualities, and multiple considerations from the two aspects of physique and physical composition may be necessary to evaluate the physical strength of students in each grade.

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This research was conducted to assess the positive effect of the ergonomics work station on the health impairment and electrical energy usage at the woodworking workshop in Bali, Indonesia. Woodworking workshops are dangerous, particularly when they are used improperly. Workers are exposed to health hazards that cause health impairment and inefficiencies in their work conditions. A preliminary study at a woodworking workshop at the Bali State Polytechnic showed that the work station was not suitable to body size of the participants and caused awkward postures. In addition, there was also an inappropriate physical work environment. Both inappropriate work station and physical work environment caused participants to be less active and motivated. This paper reports on an experimental study into the effects of an ergonomic intervention at this workshop. The participants were 2 groups of male students with 10 participants in each group. The first group performed the task with the original work station as a control group, while the second group performed the task with the new work station. The study found a significant difference between groups (p < 0.05) both for the health impairment and the electrical energy usage. The ergonomics intervention on the work station decreased the working heart rate (16.7 %), the total score of musculoskeletal disorders (17.3 %), and the total score of psychological fatigue (21.5 %). Furthermore, it also decreased the electrical energy usage (38.7 %). This shows that an ergonomics intervention on work station decreased the health impairment and saved electrical energy usage. It also protected the workers from woodworking hazards and allowed participants to perform their tasks in healthy, safe, convenient and efficient work conditions.

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The objective of this study was to investigate the effect of upper limb postures on discomfort by repetitive gripping tasks. In the present experiment, the three levels of the upperarm abduction angle (0°, 45°, and 90°) with three levels of the elbow flexion angle (45°, 90°, and 135°) were taken as independent variables to find the effect on discomfort by repetitive gripping (150N+5N) at 15 exertions per minute. Eighteen (participants)× three (upper arm abduction angles) x three (elbow flexion angles) custom design of the experiment was used for the analysis of variances (ANOVA). The perceived discomfort score on 10° mm visual analogue scale was recorded as a dependent variable. The results showed that there was significant effect of elbow flexion angle on discomfort for repetitive gripping task (p<0.001). However there was not significant difference in discomfort for the similar task for 90° compared with 135° flexion of elbow joint (p>0.05). The EMG recording of FCR muscle showed that the reduction in the mean Median Frequency was more for 45° elbow flexion angle, but the comparatively less difference was noticed for the 90° and 135° elbow flexion angles. In conclusion, elbow flexion angle has a significant effect on discomfort by repetitive gripping tasks.

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We investigated the effects of raised ambient temperature on cardiorespiratory performance in a 3-min step test. Subjects repeatedly performed the step exercise under three ambient thermal conditions. A cardiorespiratory fitness index was computed from heart rate (HR) measurements during a recovery period after the exercise. Raised ambient temperature was associated with significantly increased HR not only during the rest period before exercise but also during the recovery period. The cardiorespiratory fitness index for the high temperature condition was significantly poorer than those for the moderate conditions. The variability of the pre-exercise HR among the three thermal conditions was highly correlated with the variability of the cardiorespiratory index. These results indicate that the 3-min step test should be performed under identical ambient thermal conditions and, if necessary, cardiorespiratory fitness evaluation based on HR recovery after the 3-min step exercise should be corrected for individual acclimation states or heat stress properties.

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The aim of this study is to recommend revisions, based on empirical data, to the current curb ramp standards for keeping bicyclists safe. Four types of curb ramps were tested: (1) concrete with a 50 mm edge height, (2) concrete reinforced by a metal plate with a 50 mm edge height, (3) plastic with a 20 mm edge height, and (4) recycled rubber with a 10 mm edge height. Twenty subjects aged 20uu60 years ascended the curbs on a bicycle under various conditions. The angles of approach were 15°, 30°, 45°, 60°, 75° and 90°. Experiments were executed under both wet and dry conditions. We found that when approaching from an angle of 45° or more, all subjects could ascend all ramps under both conditions. From a 15° approach under wet conditions, no subjects ascended the concrete ramps. Some could not ascend at a 15° approach on the concrete ramps in dry conditions, and some could not ascend from a 30° approach on the reinforced concrete ramp in wet conditions. Bicyclists riding on roadways cannot easily ascend a curb ramp with a 50 mm edge, even in dry conditions. We thus recommend that curb ramp edge heights be lower than 50 mm.

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Chakdos in Western Indian state of Gujarat are makeshift vehicles for public transport. Such a vehicle was selected for ergonomic analysis. The objective of this study was to evaluate the design of the existing vehicle from an ergonomic viewpoint and to redesign it from an ergonomic perspective. Twelve different trips were made for the entire stretch of a journey of 12 kilometers on different vehicles. In general, the access to the vehicle was a severe problem for females, children and elderly people. The median and interquartile ranges for design and related issues and postural discomfort scores were calculated for the male and female passengers separately. The seating area was uncomfortable for the males, and for the females the median score for its design was at 4.0 indicating a gross mismatch between the seat design and the passengers. The females felt that the presence of a vertical grab rail would be very helpful, and this design factor had a high median score of 5.0 indicating its absolute necessity in the vehicle. Postural discomfort scores were measured on an 8-point scale ranging from 0 to 7, where 0 indicated "no discomfort" and 7 indicated "extreme discomfort". The male passengers had the highest median discomfort on the left side of the buttocks at 6.5 and for the females for the same zone it was at 7.0 indicating again a high degree of mismatch between the body parts and the vehicle design. In the proposed design, an attempt has been made to make the vehicle more user-friendly by proposing a new type of seating system and improving the access to the vehicle based on cognitive and physical ergonomics issues of the users.

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The purpose of this research is to examine the ways bicycles swerve off sidewalks onto roads under various conditions. Seven students, five males and two females participated in an experiment on a road with a 100-cm wide sidewalk. Footage of each participant on a bicycle evading obstacles such as a utility pole and pedestrian were taken with a video camera, while a front-wheel view of the path taken by the bicycle was recorded simultaneously with a digital camera. Twelve experimental conditions were used for each participant, consisting of all the combinations of 1) three obstacle types, 2) the side (left or right) to which the bicycle went to avoid the obstacle, and 3) two weather conditions. Based on the two recorded scenes, the path was then analyzed from the viewpoint of how the bicycle swerved to avoid hitting the obstacle. We found that the conditions of riding a bicycle with an umbrella caused a larger swerve to avoid the obstacle than those conditions when the rider did not have an umbrella. In particular, the condition in which the obstacle was a pedestrian who also had an umbrella caused the largest swerve. Furthermore, the distance required to become aligned with the sidewalk when the obstacle was a pedestrian walking toward the cyclist was longer than that for other obstacles. The swerve width data showed interesting results, including a tendency for swerve width to be wider when the obstacle was a utility pole compared with other obstacles.

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