Investigating the Industrial Worker's Refractive Errors and their Relationships with the Types of Light and the Visual Work Environment

Refractive errors are the most frequent reasons for which patients refer to ophthalmologic clinics. The previous studies have found that the factors of the environment and the type of light to illuminate it could have positive effects on the prevalence rate of refractive errors. Since there is little research about this relationship at industrial workers in Iran, we decided to investigate the industrial workers’ refractive errors and their relationships with the types of light and the visual work environment.We carried out a descriptive-analytical study on 292 male and female workers working in Mashhad industrial factories. Using clustering sampling, the subjects of the study were selected to go under investigation for their age, sex, and years of working background. Then, the study examined the relationship between these factors and refractive errors. In addition, the effects of outdoor and indoor working environments as well as natural and artificial (florescent) light on refractive errors were determined by a specialist. Interesting results were obtained through statistical analyses such as Chi-Square, Fisher Exact Test and ANOVA.The results suggest that the subjects of the study ranged from 23 to 63 years old with an average age of 40±9.1. Also, their working background of an average of 16±9.3 years has showed a positive effect on refractive errors (P=0.039). Among the subjects of the study, 30 (10.3%) were diagnosed as suffering from refractive errors in one eye, 150 (51.4%) in both eyes and the other 112 subjects (38.3%) had no refractive errors. The results of investigating the symptoms accompanying refractive errors were found in the following order of prevalence: Red eye (28%); Ptergyume (17.5%); Hyperemia (16.1%); Burning (12.4%); Lacriamtion (11%) and others (15%). There was no significant difference, in terms of age, between the subjects having refractive errors and those without them (P=0.842). There wasn’t any significant relationship between age and refractive errors, either (P=0.896). However, outdoor environment (P=0.014) as well as natural light (P=0.016) were found to have had positive effects on the subjects’ refractive errors.Although the duration of working background has found to be positively effective on refractive errors, the subjects’ age hasn’t showed such effect. Natural light and outdoor work environment have had significant relationships with the subjects’ refractive errors. As for accompanying symptoms, Red eye (28%) was the most frequent.