Assessment of mental workload by the Nasa-Tlx method and its relation to the frequency of accidents at the Parsian Tuna Fish FactoryToning Zagros Parsian Factory in 2017

Nowdays, mental workload is one of the most important issues in the workplaces.Various factors affect the cognitive capacities of individuals which may lead to human errors. Due to the nature of the work and the use of tools and equipment in the tuna fish factory, the risk of accidents increases as a result of human error.The purpose of this study was to investigate the type of accidents and the relationship between the accidents and mental workload in the tuna fish factory. This cross-sectional and descriptive-analytical study was carried out on all of the 48 employees of the Zagros Parsian Factory. Nasa-Tlx questionnaire was used to collect data. Accident statistics were obtained through self-reported and recorded accident documents. Data were analyzed by SPSS software using t-test, linear regression, one-way ANOVA and Pearson correlation. The results showed a significant relationship between sex and the rate of the accidents (P-Value<0.009). The Accident requency Rate (AFR) determined to be 195. The average of the mental workload was higher than the desired 50% level. The mean of accidents in women (27.82) was higher than that of the men (16.46). There was a significant relationship between the frequency of accidents and the total mental workload (P-Value<0.04). This significant relationship was observed in the production saloon (P-Value<0252). Also, regarding the mental workload subscales, there was a significant correlation between the performance and mental workload (P-value<044) and the amount of boredom and mental workload (P-Value<0.0001). According to the results of this study, mental workload is likely to affect the frequency of accidents. Therefore, implementing a program to modify the mental workload, such as revising the work hours and resting periods seems necessary