Environmental factors—including climate, temperature, humidity, air quality, pollution, visible light, and UVR levels—may impact significantly on Healthy Sight. They can be external (ie, outdoors) or internal (ie, indoors). By their very nature, environmental factors tend to be variable and are often not easily manipulated. Healthy Sight Counseling considers these factors and their effects on visual function and ocular health and offers options to help modulate them to encourage Healthy Sight.
An important example of an external environmental factor is climate, which is a crucial determinant of potentially harmful exposure to solar radiation and glare. Another is air quality, where high levels of airborne irritants, allergens, or pollutants can lead to ocular irritation, manifested by diverse symptoms varying from epiphora to a dry eye state. In indoor workplace environments, such variables as the type and level of indoor lighting, office ventilation, and computer use can lead to eye strain, ocular fatigue, and "visual" headaches.
The focus of this page is on the immediate effects of environmental factors on the individual, as opposed to the chronic and cumulative effects of such environmental factors as ultraviolet and high-wavelength visible light over time. For information about Environmental Factors and Healthy Sight in the Future, click here.