Glare Disability and Driving Safety

Abstract

Purpose: Increasing investigation of the visual elements of safe driving environments may be of great benefit to society. Visual disability appears to be only one of many visual factors related to traffic accidents. The purpose of this article was to examine the type of visual impairment mediated by the increased glare sensitivity in adult drivers using the original halometer glare test. Methods: In this article, the visual sensory, cognitive and motor functions relevant to driving, their measurement, the epidemiology and prevention of age-associated functional impairments and the relationship of functional impairments to both self-reported driving and the imposition of legal restrictions are reviewed. Results: The problem of night and tunnel driving is the most urgent in relation to the effects of glare from vehicle headlights on motion perception of drivers. The reduced mesopic vision and increased sensitivity to glare are accompanied by an increased risk of nighttime accidents. Elderly drivers and patients with beginning cataract cannot sufficiently fulfill the criteria for night driving ability because of contrast and glare sensitivity. It is indispensable for the parameters mentioned to be carefully measured and for drivers to be informed that night driving ability may be impaired, even if visual acuity is sufficient. Conclusions: It would be advisable for traffic safety if simple tests for contrast and glare sensitivity were implemented for vehicles and/or were regularly added to the requirements for a driver’s licence, at least for older drivers. The age, functional status and test result limits should be defined to avoid a risk factor in traffic.

Cataracts and the aging driver

“…The authors concluded that a severe contrast sensitivity deficit due to cataract in even one eye increases the risk of at-fault crashes among older drivers. This finding is consistent with the suggestion that drivers with cataracts are at increased risk for nighttime accidents due to their greater vulnerability to glare, and that tests for glare sensitivity and/or contrast sensitivity might be helpful for assessing the magnitude of that risk (Babizhayev, 2003).…”

Measuring contrast sensitivity in normal subjects with OPTEC® 6500: influence of age and glare

“…Mainly persons who are older than 50 years have a reduced visual acuity by glare conditions at night [3,43]. It can be due to flocculated particles in the vitreous body and increased lens density [27].…”

Predicting the Effects of Disability Glare on Driving Performance

“…Most drivers are aware that approaching headlights or a low sun can make it more difficult to see objects outside their vehicle and some even avoid high-glare situations (Wolbarsht, 1977). Although it has been suggested that glare susceptibility testing might be used to identify drivers who are especially disabled by glare (Wolbarsht, 1977;Regan, 1991;Babizhayev, 2003), a causal connection between laboratory measures of an individual's glare susceptibility and the probability for accidents in high-glare conditions is lacking. It is even the case that the extent to which glare affects driving performance is not known: "Glare problems are often discussed as a serious threat to the safety of older drivers.…”

“…However, no studies have demonstrated that increased disability glare is independently associated with either crash involvement or self-reported difficulty in driving (pg. 21)" (Babizhayev, 2003). These are important gaps in our knowledge, given that a high level of glare susceptibility is common in older individuals (Allen, 1967;Regan, 1991), especially in those with early cataract (Miller & Benede, 1973;Regan, Giaschi & Fresco, 1993) and that it is projected that the proportion of drivers over the age of 65 will continue to increase over time to roughly 1 in 5 by the year 2030 (NHTSA, 2006).…”