What is meant by eye strain?
Eye strain, also known as asthenopia, can manifest as tired eyes, difficulty focusing, or discomfort after visually demanding tasks. Dry eyes can also occur when working with screens. Not all of these symptoms have the same cause, nor should they be automatically attributed to the monitor.
Focusing demands, readability, glare, and environmental conditions can all play a role. There may also be a need for vision correction or other issues requiring medical evaluation. Persistent, recurring, or vision-impairing discomfort should be addressed by a doctor; adjusting screen brightness is not a substitute for proper evaluation when needed.
Task demands and exposure time
Working with screens encompasses a wide range of activities: continuous reading, reviewing plans, data entry, and comparing documents across multiple screens. What matters is what the person needs to distinguish, at what distance, and with what precision, in addition to the amount of time spent using them. A single number of hours only partially describes the demands.
It’s also important to consider whether the task requires constantly shifting focus, consulting small print, or maintaining intense attention without interruption. A poorly designed application can create avoidable demands. The evaluation should consider the software and documents used, because a technically adequate screen doesn’t guarantee that the information will be presented legibly.
Lighting, reflections and contrast
The lighting should allow you to see the task without discomfort from excessive contrast or glare. The position of windows, light fixtures, and surfaces influences the result. Glare can force you to change your posture, squint, or make an extra effort to distinguish details.
It’s advisable to check the workstation at different times, as natural light varies. Solutions may include repositioning equipment, controlling the amount of light entering the room, or adjusting task lighting. Darkening the entire room to compensate for glare can create other problems. The solution should address the underlying cause and maintain suitable conditions for other activities.
Adjust the equipment to the person
The font size, contrast, resolution, and window layout should allow for comfortable work without repeatedly leaning closer or adopting awkward postures. The screen distance and height are adjusted based on the task, vision, and use of corrective lenses. There is no single configuration that will be suitable for all people and applications.
In workstations with multiple screens, it’s important to position the main screen according to its actual use and avoid unnecessary visual shifts. Frequently consulted documents also need to be easily accessible. Tools like the ROSA method can support a review of the office workstation, but their results should be interpreted in conjunction with the specific visual demands and observations of the user.
Organization, alternation and recovery
Breaks and recovery time should be tailored to the specifics of the job. Switching from a spreadsheet to a mobile phone can maintain a similar level of close visual demand. Effective alternation involves varying the demands whenever possible, as well as allowing for breaks before fatigue sets in.
In Spain, Royal Decree 488/1997 allows for reducing continuous screen time through changes in activity or breaks when required by job evaluation. It does not establish a universal guideline of minutes applicable to all positions. The organization must facilitate the agreed-upon measure, ensuring that objectives or customer service do not prevent its use.
Health surveillance
Health surveillance must consider visual risks along with physical and mental workload risks. For individuals covered by Royal Decree 488/1997, it must be offered before starting work, at intervals adjusted to the risk, and whenever disorders appear that could be related to this work.
The standard also includes provisions for eye exams when the results warrant it, and special corrective devices under the established conditions. This does not mean recommending the same glasses or filters for all employees. The need is determined through a proper assessment, and clinical data must be kept separate from the preventive information the company receives.
Practical example
In a hypothetical administrative department, complaints are received about eye strain when reviewing digitized documents. The analysis reveals low-quality files, texts reduced to fit two pages, and reflections from a window during part of the morning. The initial proposal to replace all monitors alone does not explain these issues.
The quality of the documents is improved, a legible display is configured, and their positioning relative to the window is corrected. Some tasks are also reorganized to interrupt prolonged review periods. The results are then reviewed with users, and health assessments are provided to those experiencing discomfort. The measure is adapted to observed needs, not a generic purchase.
How to check for improvement
The review should verify that settings are maintained, that applications allow for legible font sizes, and that alternation measures are used. It’s advisable to record when problems arise and in which tasks, without turning this monitoring into individual productivity tracking. The observations should be used to correct workstation conditions.
Persistent discomfort necessitates a reassessment of the evaluation and an assessment of other causes. A technical improvement may be insufficient if pressure to work without interruptions persists. The goal is for equipment, environment, and organization to allow tasks to be performed with reasonable visual demands and for each person to receive the healthcare they need.
