Driving Flashcards
What are some examples of low contrast targets?
Pedestrians with dull clothing
Dull coloured cars
Dirty number plates
When are contrast levels lower?
Night
Rain
Fog
Dirty windscreen
Who do Group 1 Visual Standards apply to?
Car and motorbike drivers
What are the terms of group 1 visual standards?
Can use specs or CLs
Tests performed in daylight
Only verified at test and at 70
DVLA must be informed if there is a problem which could cause visual problems.
What distance should the number plate test be performed at?
20m
5 car lengths
8 parking space widths
What is the VA needed to be able to drive a group 1 vehicle?
6/12 binocularly (monocularly if one eye)
What are the advantages of the number plate test?
Easy to administer (can self monitor)
Can be tested at incident site
What are the disadvantages of the number plate test?
Variable lighting
Number plates can be dirty (reduced CS)
Large testing distance
Symbol design causes crowding on new plates (since 2001)
What are grandfather rights?
Those who passed their test before 1997 can drive more vehicles, and can drive a bus/lorry if monocular
What are the recommendations for mobility scooters?
Class 3 allowed on the road (8mph max)
No legal vision standard but recommended to read number plate at 12.3m
What are the minimum visual field standards for group 1?
Horizontal: 120 degrees, 50 R&L
Vertical: 20 degrees
No defects within central 20 degrees
What visual field test is required for vision standards and what settings are required?
Binocular Estermann (10dB)
3mm target at 0.3m
Goldmann III4e white setting (or equivalent)
What characteristics of diplopia prevent driving?
Primary position diplopia which is v hard to overcome (can use patch or prism for group 1, prism only for group 2)
Diplopia due to stroke - no driving for 1 month
Is monocularity allowed for group 1?
Yes, but adaptation period of no driving required if sudden onset
What is allowed during a binocular Estermann fields test?
Max 3 attempts
False positives below 20%
Scattered single missed points
Single cluster of up to 3 adjoining points
What is unacceptable on a binocular Estermann fields test for group 1?
Central clusters of 4 or more missed points (wholly or partially within central 20 degrees).
Cluster of 3 missed points up to/including central 20 degrees with additional missed points within central 20 degrees.
Any central loss which is an extension of hemianopia/quadrantanopia or larger than 3 missed points.
Who does group 2 visual standards apply to?
HGV and 10+ passenger vehicles
What limits do group 2 drivers have?
Rx can’t be over +8D in specs (no CL limit)
Binocular (unless grandfather rights apply)
No diplopia
No other impairment of visual function e.g. glare.
How often should a D4 be renewed?
Every 5 years
Every year if over 65
What are the VA requirements for group 2 drivers?
6/7.5 in better eye
6/60 in worse eye
No worse than 3/60 uncorrected
What are the minimum visual field standards for group 2?
Horizontal: 160 degrees, 70 R&L
Vertical: 30 degrees
No defects in central 30 degrees
What is acceptable field loss for group 2 drivers?
Single cluster of up to 3 points outside central 30 degrees
3 or less single missed points
What does the dynamic VA test test?
VOR - ability to perceive moving letters while moving head
What are the disadvantages of the dynamic VA test?
Poor repeatability
Little difference shown between high and low rate accident drivers
