A study on visual discomfort among workers performing tedious visual tasks

Abstract

Visual problems such as eyestrain and irritation are among the most frequently reported complaints by Display Screen Equipment (DSE) operators (OSHA, 1997). DSE work is more sedentary, requires more mental processing but less physical use of energy (Mocci, Serra, Corrias, 2001). Workers having the roles of tedious visual tasks, like visual inspection, for a considerable number of hours may be subjected to the same ill-health effects associated to eye-strain among DSE users. In the occupational context, visual inspection usually forms part of the quality assurance regime and consists of visually checking manufactured products for any aesthetical defects present, against a pre-defined criteria. Defects may vary from those anomalies affecting the functionality of the product like deformation, missing and extra pails, etc to purely aesthetical defects which affect the way a product looks or is seen like discolouration, asymmetry and other defects making it less appealing to the user. This study was aimed to measure visual symptoms amongst visual inspectors in the manufacturing industry who spend a significant number of continuous working hours on visual tedious tasks. The results were then compared against other results found in the literature review of studies on eye fatigue amongst DSE workers. The results would show if there can be association of the same visual symptoms between both jobs. The rationale behind the association of both contexts was the similarity of basic factors, mainly: • both jobs are done in a sitting position at a work station • in both jobs, the eyes are the parts of the human body that are most used (apart from the brain) • both jobs require the worker to continuously look at an illuminated object. The results showed that visual inspection tasks do cause eye strain complaints amongst workers carrying out such duties and that amongst other factors, the nature of the task makes a difference to the severity of the symptoms with regards to the material of the product, the shape and the inspection criteria. Thus, the study proved that the visual symptoms which are usually associated to the DSE workers and which are often studied and found in lots of published literature, may as well be associated to workers assigned to visual inspection of manufactured products about whom not so many literatures can be found. Although, the samples used were relatively small with respect to the population of workers carrying out such visual tasks, the results can serve as a springboard for other major studies in this area.