This study evaluates a new equation for defining maximum desk height in educational settings, comparing it with the traditional Chaffin and Anderson-based equation through biomechanical analysis. The new equation, based on 30° shoulder abduction and 35° flexion, was tested against established criteria in a quasi-experimental study involving 34 participants. Using motion capture and surface EMG, we analyzed shoulder kinematics and muscle activity during six standardized tasks performed at two desk heights. Results showed no significant differences in shoulder kinematics safety parameters between setups, while EMG data revealed consistent muscle activity patterns below 10 % MVC for both conditions. Performance metrics across tasks showed no significant differences between desk heights. Preference analysis indicated no overall significant difference between conditions, although gender-specific patterns emerged with 66 % of women preferring the proposed height. Discomfort levels were comparable between conditions. Theoretical testing of the new equation on existing databases (n: 2261 students; n: 2946 workers) demonstrated improved anthropometric fit, increasing match rates from 63 % to 94 % in students and reducing high mismatch cases from 46.7 % to 7.1 % in workers. The findings validate that the new equation maintains biomechanical safety while significantly improving anthropometric fit. This alignment between biomechanical and anthropometric criteria represents an advancement in educational furniture design, particularly relevant for contemporary educational tasks requiring forearm support.

This study aimed to collect and analyze three-dimensional (3D) anthropometric data of Chilean workers to support the design of personal protective equipment (PPE) tailored to their physical characteristics. A total of 2016 participants, including Chileans and migrant workers, were measured using advanced 3D scanning technology. Significant sex-based and nationality-related differences were identified, with males exhibiting larger dimensions across most measurements. Comparisons with international datasets, including CAESAR, revealed unique anthropometric features among Chilean workers, highlighting substantial deviations in head and facial dimensions. These findings underscore the need for sex-specific and population-specific PPE designs, particularly given Chile's increasing workforce diversity. The results have practical implications for improving PPE fit, comfort, and safety in the workplace. This study provides a robust 3D anthropometric database that serves as a critical resource for manufacturers and safety professionals aiming to enhance occupational safety and equipment performance.

Background:
Personal Protective Equipment (PPE) is crucial for minimizing workplace hazards, and its effectiveness relies on adapting to diverse anthropometric features.

Objective:
To establish the first 3D anthropometry database of Chilean workers. Also, this study compares 18 dimensions with the North American CAESAR three-dimensional anthropometrical scan database.

Methods:
The research utilized three-dimensional data collected from 348 Chilean individuals, ages ranging between 19 and 68 years old. Measurements were captured with a 3D face scanner (3dMD®) following ISO/TS 16976-2 and ISO 15535 guidelines to maintain rigorous standards.

Results:
Noticeable sexual dimorphism: Chilean males exhibit larger facial dimensions than females, such as Nose breadth and Face length, which emphasize the need for gender-specific PPE designs. Furthermore, comparisons with the CAESAR dataset revealed significant disparities among Chilean and other populations, emphasizing the importance of ethnic tailoring PPE. The implications for respiratory PPE design are substantial; variations in dimensions like Face length and Face width highlight the need for adjustable or size-specific respirators.

Conclusions:
The study underlines the importance of considering not only gender-specific differences but also ethnic variations in PPE design. The findings emphasize the critical role of anthropometric data in developing tailored respiratory protection devices, ensuring effective workplace safety across diverse populations. The study recommends further research to validate the findings in other populations and to advocate for inclusive design practices in occupational safety.