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Updated: Oct 8, 2026

Measuring the Mechanical Properties of Glass Fiber Reinforcement Polymer Composite Laminates Obtained by Different Fabrication Processes
Published on: June 30, 2023
[Work conditions and automation: the case of glassblower]
1Universidade Metodista de São Paulo, São Paulo, SP, Brasil. fatiquei@usp.br
Objective:
To investigate how the use of different technologies, organizational structures, and task control determine the health-disease process in workers.
Methods:
The study was developed in two glass industries, one automated and the other manual, in the city of S. Paulo, Brazil, between 1996 and 1997. Ergonomics methods were used as main principles underlying the techniques of data collection. The techniques applied were case study and group comparisons, including a direct observation of the work condition, interviews and a questionnaire answered by all 41 workers of the workplaces studied: operators of automated machines (27 workers) and manual glass blow operators (14 workers). The questions were about their jobs and workplace characteristics and health complaints. The data were analyzed using Epi Info 6.
Results:
The comparison between the two group of workers showed statistically significant differences in relation to workers' perceptions about excessive noise, work tools, posture while performing their work and complaints of pain in the arms. There were also identified differences in risk factors: movement repetition seen in the manual industry and those related to work organization in both industries, such as work rhythm, employees' participation in important decisions and training.
Conclusions:
The use an ergonomics methodology was perfectly adequate. Manual industry workers seem to play a role that makes them feel they have an important participation in the work process, as they performed a significant part of the total work, contrasting with automatic industry workers, which task is only of supervising the process, where the machine is the actual producer.
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