Secular changes in the anthropometrics of Chilean workers and its implication in design.

BACKGROUND: Anthropometrics is very important when ensuring a physical match between end users and product or workstations. OBJECTIVES: The purpose of this study are twofold, to provide anthropometric data for the design of products and to examine the secular changes in the adult Chilean workers in a period of more than 20 years. METHODS: Nineteen anthropometric measurements from two samples from 1995 and 2016 were compared using independent t-test (95% confidence interval), where additionally absolute and relative differences were calculated. RESULTS: The secular trend observed for Stature is characterized by an increase average of 20mm and 10.5mm per decade for females and males, respectively. There is a positive secular trend for both genders, which is observed for most of the selected body measurements. The most pronounced increases were onWeight, Shoulder breadth, Body mass index, Popliteal height; Buttock-popliteal length and Hip width. CONCLUSIONS: Segmental dimensions that experienced a positive secular trend, together with Weight and Stature, are highly correlated with seating design, addressing the need to review products targeting Chilean adult workers, such as public transport seats, office furniture or industrial workplaces.

Anthropometric characteristics of Chilean workers for ergonomic and design purposes.

Obtaining an appropriate match between a product and its end-users requires anthropometric data, which are typically outdated and show variations among different countries. Chile had its anthropometric data taken nearly 20 years ago, thus they are probably outdated. The purpose of this article is to describe some anthropometric characteristics of Chilean workers. An anthropometric survey involving 27 measures and five calculated body dimensions was conducted in 2016. The measurements were based on ISO 7250 and ISO 15535 to ensure the highest standards possible, and a total of 2946 workers, aged from 18 to 76 years old, participated in the survey. The results showed that Chilean workers have smaller dimensions than Dutch and US workers but have larger dimensions than South Koreans. The data presented in this article constitute the most up-to-date anthropometric dataset describing the dimensions of Chilean workers. Practitioner Summary: In Chile, women are smaller and weigh less than men, and both of these populations have high body mass index (BMIs). In addition, the Chilean population exhibits substantial differences compared with other international adult populations. The data presented in this article should be used as a reference when designing for Chilean workers.

A literature review of anthropometric studies of school students for ergonomics purposes: Are accuracy, precision and reliability being considered?

BACKGROUND: Despite offering many benefits, direct manual anthropometric measurement method can be problematic due to their vulnerability to measurement errors. OBJECTIVE: The purpose of this literature review was to determine, whether or not the currently published anthropometric studies of school children, related to ergonomics, mentioned or evaluated the variables precision, reliability or accuracy in the direct manual measurement method. METHODS: Two bibliographic databases, and the bibliographic references of all the selected papers were used for finding relevant published papers in the fields considered in this study. RESULTS: Forty-six (46) studies met the criteria previously defined for this literature review. However, only ten (10) studies mentioned at least one of the analyzed variables, and none has evaluated all of them. Only reliability was assessed by three papers. Moreover, in what regards the factors that affect precision, reliability and accuracy, the reviewed papers presented large differences. This was particularly clear in the instruments used for the measurements, which were not consistent throughout the studies. Additionally, it was also clear that there was a lack of information regarding the evaluators' training and procedures for anthropometric data collection, which are assumed to be the most important issues that affect precision, reliability and accuracy. CONCLUSIONS: Based on the review of the literature, it was possible to conclude that the considered anthropometric studies had not focused their attention to the analysis of precision, reliability and accuracy of the manual measurement methods. Hence, and with the aim of avoiding measurement errors and misleading data, anthropometric studies should put more efforts and care on testing measurement error and defining the procedures used to collect anthropometric data.

Hand luggage in the train toilet.

BACKGROUND: The train toilet can form a barrier for those wishing to travel by train as it is perceived as being dirty, and therefore its use as being unpleasant. In addition, Dutch train toilet users have the additional issue of storing their hand luggage in the toilet's confined spaceOBJECTIVE:In this article, we examine the issue of Dutch travelers with hand luggage in relation to their use of train toilets. We investigate the type of hand luggage train travelers have with them and lastly, we study what travelers do with their hand luggage when using the toilet. METHODS: As part of an overarching study, we asked two specific questions on what travelers do with their hand luggage in a train toilet environment, followed by 22 observations from observational research. RESULTS: In the questionnaire, train travelers reported that bringing hand luggage into the train toilet is a problem because of the lack of storage space, and their fear of losing their seat. From the observational research, we noted that the participants mainly held their hand luggage on their bodies, and to a lesser extent, they placed it on the floor of the train toilet itself. None of the 22 participants used the hook to hang up their bag and/ or their coat. CONCLUSIONS: Travelers need a facility in the train toilet to store their hand luggage. Women have a stronger need for this than men, as they almost always carry an item with them. In addition, they use the toilet in hovering position or seated, with their backs to the wall, so they have limited space to store hand luggage on their backs or shoulders as men do. Most participants kept their hand luggage at a distance from the bowl, and the majority kept it off the floor (14 of the 22) because they were aware of the hygiene. The positioning of the coat/luggage hook at 1840 mm above the floor was considered to be too high, out of people's comfort area.

Thirty years of anthropometric changes relevant to the width and depth of transportation seating spaces, present and future.

This paper reports the results of an investigation into changes in body shape anthropometry over the past several decades and discusses the impact of those changes on seating in transport, especially airliners. Changes in some body shape dimensions were confirmed in a sample of students at TU Delft; several of the changes, e.g. hip breadth, seated, are relevant to the ongoing design of seating. No change in buttock knee length was observed. The fit between current user anthropometry and current airline seat design, especially regarding seat width, was investigated. A comparison of the average current seat breadth with global anthropometric data suggests that accommodation may be problematic, with less than optimal width for passengers' shoulder and elbow widths.

The influence of school furniture on students' performance and physical responses: results of a systematic review.

The purpose of this study was to determine, using a systematic review, whether the design and/or dimensions of school furniture affect the students' physical responses and/or their performance. Of the review studies, 64% presented positive results, i.e. proven effects; 24% presented negative effects or no change/effect; and the remaining 12% showed an unclear effect. The compatibility between school furniture dimensions and students' anthropometric characteristics was identified as a key factor for improving some students' physical responses. Design characteristics such as high furniture, sit-stand furniture, and tilt tables and seats also present positive effects. Finally, we concluded that further research should be conducted exploring various aspects of those variables, particularly focusing on more objective measures complemented by controlled and prospective design. Practitioner Summary: A systematic review of the literature presents a clearly positive effect of school furniture dimensions on students' performance and physical responses. Similar results appeared when school furniture design was tested. However, studying the effects of design and dimensions together produced an unclear positive effect.

The effect of secular trends in the classroom furniture mismatch: support for continuous update of school furniture standards.

In order to create safer schools, the Chilean authorities published a Standard regarding school furniture dimensions. The aims of this study are twofold: to verify the existence of positive secular trend within the Chilean student population and to evaluate the potential mismatch between the anthropometric characteristics and the school furniture dimensions defined by the mentioned standard. The sample consists of 3078 subjects. Eight anthropometric measures were gathered, together with six furniture dimensions from the mentioned standard. There is an average increase for some dimensions within the Chilean student population over the past two decades. Accordingly, almost 18% of the students will find the seat height to be too high. Seat depth will be considered as being too shallow for 42.8% of the students. It can be concluded that the Chilean student population has increased in stature, which supports the need to revise and update the data from the mentioned Standard. PRACTITIONER SUMMARY: Positive secular trend resulted in high levels of mismatch if furniture is selected according to the current Chilean Standard which uses data collected more than 20 years ago. This study shows that school furniture standards need to be updated over time.

Analysis of the most relevant anthropometric dimensions for school furniture selection based on a study with students from one Chilean region.

Most of the worldwide standards used for furniture selection suggest the use of the Stature of the school children, assuming that all the other anthropometric characteristics will also be appropriate. However, it is important to consider that students' growth differ with age. The aim of this study is to determine if Popliteal Height can be used as a better, or more adequate, measure for classroom furniture selection when comparing with Stature. This study involved a representative group of 3046 students from the Valparaíso Region, in Chile. Regarding the methodology, eight anthropometric measures were gathered, as well as six furniture dimensions from the Chilean standard. After assigning the level of school furniture using Stature and Popliteal Height to each of the students, six mismatch equations were applied. The results show that when using Popliteal Height, higher levels of match were obtained for the two more important furniture dimensions. Additionally, it also presents a better cumulative fit than Stature. In conclusion, it seems that Popliteal Height can be the most accurate anthropometric measure for classroom furniture selection purposes.

Evaluation of the match between anthropometric measures and school furniture dimensions in Chile.

BACKGROUND: Students are exposed to the first systematic tasks or activities that a human being carries out in his/her life while at school. In this workplace situation, school furniture is a key factor for the adoption of proper body posture. OBJECTIVE: The aim of this paper was to observe and determine the potential mismatch between school furniture dimensions and anthropometric characteristics of the students from the Valparaíso region of Chile. METHODS: The sample consisted of 3,078 volunteer participants from 18 schools (public, semi-public, private). Eight anthropometric measures were gathered, together with six furniture dimensions. Mismatch analyses were carried out by using pre-defined mismatch criteria. RESULTS: Many different types of school furniture were presented at the schools. Also, a high level of mismatch was registered for seat height, desk height and seat-to-desk clearance. Finally, the analysis of all considered dimensions together showed that there was a high level of cumulative mismatch. CONCLUSIONS: It can be concluded that there were high levels of mismatch between the school furniture and student anthropometric characteristics and that this mismatch varied within the difference types of schools. This situation may have occurred because furniture acquisition was made without considering any ergonomic criteria.

Applying different equations to evaluate the level of mismatch between students and school furniture.

The mismatch between students and school furniture is likely to result in a number of negative effects, such as uncomfortable body posture, pain, and ultimately, it may also affect the learning process. This study's main aim is to review the literature describing the criteria equations for defining the mismatch between students and school furniture, to apply these equations to a specific sample and, based on the results, to propose a methodology to evaluate school furniture suitability. The literature review comprises one publications database, which was used to identify the studies carried out in the field of the abovementioned mismatch. The sample used for testing the different equations was composed of 2261 volunteer subjects from 14 schools. Fifteen studies were found to meet the criteria of this review and 21 equations to test 6 furniture dimensions were identified. Regarding seat height, there are considerable differences between the two most frequently used equations. Although seat to desk clearance was evaluated by knee height, this condition seems to be based on the false assumption that students are sitting on a chair with a proper seat height. Finally, the proposed methodology for suitability evaluation of school furniture should allow for a more reliable analysis of school furniture.

User-centered ecotourism development.

The transfer of knowledge in an ecotourism project is never a one-way affair. An approach connected to bottom-up development is the submersion into another culture, while creating a new organizational structure. For co-creation, patterns that are often latent, such as leadership roles, the association with business, or even the color of education can be revealed by carefully facilitated brainstorms or workshops. Especially in countries with a different hierarchical structure, such as Indonesia compared to Holland, a careful analysis is needed before starting cooperation. Although a case is only a temporary view on a situation and not a guarantee for a truly sustainable system, the bottom-up approach tested has interesting starting points for an ecotourism system. Two cases were conducted in Bali, Indonesia, which resulted in guidelines on how to approach user-centered ecotourism development.

Representation of a human head with bi-cubic B-splines technique based on the laser scanning technique in 3D surface anthropometry.

Three-dimensional (3D) anthropometry based on the laser scanning technique not only provides one-dimensional measurements calculated in accordance with the landmarks which are pre-located on the human body surface manually, but also the 3D shape information between the landmarks. This new technique used in recent ergonomic research has brought new challenges to resolving the application problem that was generally avoided by anthropometric experts in their researches. The current research problem is concentrating on how to shift and develop one-dimensional measurements (1D landmarks) into three-dimensional measurements (3D land-surfaces). The main purpose of this paper is to test whether the function of B-splines can be used to fit 3D scanned human heads, and to for further study to develop a computer aided ergonomic design tool (CAED). The result shows that B-splines surfaces can effectively reconstruct 3D human heads based on the laser scanning technique.

Revision of the design of a standard for the dimensions of school furniture.

In this study an anthropometric design process was followed. The aim was to improve the fit of school furniture sizes for European children. It was demonstrated statistically that the draft of a European standard does not cover the target population. No literature on design criteria for sizes exists, and in practice it is common to calculate the fit for only the mean values (P50). The calculations reported here used body dimensions of Dutch children, measured by the authors' Department, and used data from German and British national standards. A design process was followed that contains several steps, including: Target group, Anthropometric model and Percentage exclusion. The criteria developed in this study are (1) a fit on the basis of 1% exclusion (P1 or P99), and (2) a prescription based on popliteal height. Based on this new approach it was concluded that prescription of a set size should be based on popliteal height rather than body height. The drafted standard, Pren 1729, can be improved with this approach. A European standard for school furniture should include the exception that for Dutch children an extra large size is required.