Legal Distance for Reading a Number Plate
It has been shown that the ability to read the licence plate does not depend on the background colour if the licence plate is clean. There is no exact critical sharpness of the Snellen diagram that meets the license plate standard. Drasdo and Haggerty2,3 found that applying a standard of 6/9â2 (6/10) resulted in a mathematical equivalent (i.e., this standard lacked the same proportion of people, but not necessarily the same person). This visual acuity of 6/10 corresponds to a decimal acuity of 0.6, which is in fact a visual acuity higher than that required by the European standard 4 of 6/12 (decimal 0.5). Although the European standard for monocular drivers provides for a visual acuity of 6/10 (decimal 0.6) and the UK does not distinguish between visual acuity for single and binocular drivers, it could be said to comply with the Directive. Charman5 calculated that the license plate symbol submerged a viewing angle of about 13.3 arc minutes, meaning that the nominal binocular visual acuity is actually about 6/15. This is confirmed by simple geometry (see Figure 1) and represented by a letter on a theoretical line of the Snellen diagram about halfway between lines 6/12 and 6/18. The license plate test is an easy and effective way for people to verify that their vision meets the standards required for driving. The easiest and quickest way to do this is to find out what 20 meters look like on the side of the road – that`s usually the length of 5 cars parked next to each other – and then test yourself to see if you can read the license plate clearly. It is a simple check that can be done at any time of the day on the side of the road and only takes a few seconds. In the first part of the study, all three license plates were ranked in the order of their first reading and these results were statistically analyzed using the Friedman test. This tests the null hypothesis that the variables related to k come from the same population.
This value of 6/15 is a standard of static visual acuity lower than that stated by the Royal College of Ophthalmologists of about 6/10. In our study, of the seven subjects who could not read any of the license plates at 20.5 âm, six (85.7%) had a static visual acuity of 6/12. This confirms the level of 6/10 chosen by the Royal College of Ophthalmologists for an approximate level of static visual acuity. The police vision test on the side of the road is the same as the vision test at the beginning of a practical driving test, as the driver is asked to read a license plate 20 meters away. If you have trouble reading license plates at this distance and they seem a little blurry, you`ll almost certainly need glasses or contact lenses to drive. Kiel, A., Butler, T. & Alwitry, A. Visual acuity and legal requirement of sight to drive a private car. Eye 17, 579-582 (2003). doi.org/10.1038/sj.eye.6700441 The standard of static visual acuity required of ordinary drivers is the ability to read, in good lighting (using glasses or contact lenses, if worn), a licence plate attached to a motor vehicle containing letters and numbers 79.4 mm (31/8 inches tall) at a distance of 20.5 m (67 inches). This standardised registration plate check is described in the Motor Vehicle Ordinance (Driving Licence Ordinance) and the Road Traffic Act 1989.
The agency found that only 48.5% of drivers surveyed were aware of this essential visual requirement. Now that more drivers will resume their daily commutes, go to school and traffic will return to pre-pandemic levels, the agency is urging drivers to make sure they pass the 20-metre license plate test. Key outcome measures The ability to read three different licence plates under standard DVLA driving test conditions (i.e., at 20.5 âm in broad daylight with glasses if worn) and the ability to read identical licence plates on a white and yellow background. In the second part of the study, the ease of reading the license plate on a white background was compared to reading on a yellow background. The results were analysed with an Ï2 (Ï2=0.476, df=1, asymp. sig. 0.490). The College of Optometrists recommends that people over the age of 16 have an eye test every two years or more frequently if they have eye problems.
Another way to check your eyesight solely for driving purposes is to try the police driving test yourself. While a measuring tool is obviously the most accurate way to determine distance, the DVLA still recommends using a series of five parked cars or eight parking spaces as an alternative “easy way to measure distance.” The lack of standardization in license plate testing has often been criticized.2,3,6,7 The test contains several possible confounding variables, including lighting, license plate constituent features, license plate background, and even cleanliness, which can affect the contrast and visibility of each symbol. Drivers with limited visibility are at higher risk of collision with a pedestrian or other vehicle. If a driver can`t read the road far enough ahead, they`ll see fewer pedestrians, animals, parked cars, or the brake lights of other vehicles until the last moment, shortening their reaction times and increasing the risk of accidents. Drivers with poor peripheral vision may have difficulty seeing vehicles passing them or approaching from the side. In addition, vision problems that lead to poor depth perception can make it difficult to evaluate stop and parking routes. And that`s more than 15 feet closer — a car length — than when the eye test was introduced in 1937 at a distance of 75 feet (23 m). The height of a letter on the license plate at 20.5 âm would be less than the same angle at 6 âm if it were 23.24 ° mm high.
In broad daylight, you must be able to read a license plate from a distance of 20 meters (or at a distance of 20.5 meters for old license plates). Theoretically, a visual acuity of about 6/15 is required to pass the standardized test. In our population, all patients had a minimum visual acuity of 6/12 and therefore all should have been able to read each of the license plates comfortably at a legal distance. In our study, 93.2% of patients were able to read all plaques. This was a higher proportion compared to the study by Currie et al.8, where only 74% of subjects with a visual acuity of 6/9 and only 66% of subjects with a visual acuity of 6/12 could read the license plate. This can be explained by the use of a group of older subjects with a higher degree of cataract formation, lower contrast sensitivity and more glare problems. The license plates in our study were all clear and clean, which made viewing easier and gave subjects enough time to read them. In the second part, the null hypothesis was proposed that there is no difference between reading a licence plate on a white background and a yellow background. These results were then analysed using the Ï2 test. This article highlights the inherent variability of the current method of visual acuity testing and the lack of standardization of this assessment in the context of the driving test.
With the new license plates, which are composed of narrower font dimensions, and with the revised distribution of letters and numbers, which provides better visibility, the license plate test has been modified accordingly, reducing the test distance to a more memorable 20âm to match the previous undervoltage angle. It seems useful at this stage to standardise the test protocol and to cooperate with other European standards. If you want to do your own license plate test when walking down a street or parking lot, 20 meters is about 5 car lengths. The order in which the license plates became legible by participants was recorded, with the first license plate read (i.e. at the greatest distance) being given a score of 1, the second license plate a score of 2 and the last license plate read (i.e. at the shortest distance) a score of 3. “In the Motor Vehicle (Driver`s Licence) Regulations, 1937, the required distance was 25 yards or 75 feet. In 1971, the distance was changed to 67 feet (20.5 meters) to accommodate a change in license plate size. Changes: New drivers will now have to read a 57-foot license plate instead of 65-foot, while the rules for epilepsy, diabetics and seizures will also be changed. The license plate test is quick and easy to perform, and DVLA provides examples of measuring the distance of 20 meters, which is equivalent to five car lengths.
or the width of eight parking spaces. Less than half of the motorists surveyed by the DVLA know that they must be able to read a license plate from 20 meters away to drive safely.