while surfing the net i found this Hope it helps
Evaluation Criteria
Grade
S
The vehicle is less than 12 months old from the first year of registration. It doesn't require any repairs to the interior or exterior. This vehicle is suitable for exhibition selling.
6
The vehicle is less than 24 months old from the first year of registration. It doesn't require any repairs to the interior or exterior. This vehicle is suitable for exhibition selling.
5
The vehicle is very close to point 6; however the vehicle requires minor aesthetic repairs.
4.5
This vehicle is very close to point 5; however the vehicle may require some minor panel beating work or painting or interior repairs.
4
The damage on this vehicle is slightly more severe than 'point 5'. It requires repairs to damaged parts.
3.5
The vehicle has noticeable damage. It has a history of repairs to its core structure; front, back and side panels.
3
The damage to this vehicle is more noticeable than 'point 3.5'. Scratches and other damage are clearly visible.
2
The entire vehicle needs panel beating and repairs. Corrosion can be found on the vehicle. The Odometer reading is suspect and the odometer may not work. Major damage to the interior and exterior.
1
Engine still in working order, however car is in need of much repair, the vehicle can still be driven.
0
The part of the car has been changed or repaired.
R
Repaired Car
Additional Evaluation Criteria
1
Frame - Changed, in need of repair or has been repaired.
2
Floor - Changed, in need of repair or has been repaired.
3
Pillar - Each or some of the Pillars have been changed, repaired or in need of repair.
4
Car panel - Changed, in need of repair or has been repaired.
5
Inner Panel - Changed, in need of repair or has been repaired.
6
Roof - Changed, in need of repair or has been repaired. Large damage noticeable.
7
Step - Changed, in need of repair or has been repaired
8
Car body and Cabin - Original body changed.
9
Chassis number - chassis number has been officially altered. (With exception of imported cars).
10
An occasion arises where CNA concludes that a situation does not match any of the above mentioned points.
Damage Evaluation System
Body Dent
B1/E
The size of the dent is more than 1cm by 1cm. A dimple - not noticeable from side profile.
B2
A dent that you can recognize when standing directly in front - 1cm by 1cm in size.
B3
Noticeable dent - Fist size.
B4
Dent is more than 20cm by 20cm.
B5
Dent covers an entire panel or is bigger than one panel. Panel may need replaced.
Scratches
A1
under 5cm long.
A2
Less than 10cm long, covers under 1/4 of the panel.
A3
Less than 20cm long, covers under 1/2 the panel.
A4
More than 20cm, covers more than 1/2 the panel.
A5
Covers the entire panel.
P
Needs painted. E.g. AP2
Repaired and Painted
W1
Quality repair work.
W2
Slightly noticeable.
W3
Repair and/or paint work noticeable. Repair and/or paint work may need to be repeated.
Others
S
Rust
C
Corrosion
Bumper Scratch
A1
Small Scratch - approx. 1 - 2 cm.
A2
Scratch covers 1/4 of one panel.
A3
Scratch covers 1/2 of one panel.
A4
Covers more than 1/2 of one panel.
A5
Covers whole panel.
P
Needs to be painted E.g. AP3. (Only needs painted, no repairs).
Dent
U
Bent or distorted or broken
Glass
G
Visible Stone chip.
G
Wiper Scratches
G
Abrasion,/scratch
GS
Broken - size not stated.
Others
XX
Corresponding part of vehicle has been changed.
M
Corresponding part of vehicle shows evidence of changes.
Large Car Accident
Change of front and rear frame and/or roof and/or tow board and/or front floor and/or trunk floor.
Medium Car Accident
Change of inner panel and/or pillars and/or roof side rails and/or front and rear frame and/or panel beating to correct a dent, bent panel or distortion of a panel and/or evidence of repairing steps of the car and/or panel beating of the floor, (front, center and trunk.)
Small Car Accident
Change of member and/or bent rock pillar and/or changing of two sections of panel and/or welding (for example rear fender plus back panel)., and/or front or rear frame panel beating and/or front and rear inner panel beating, and/or panel beating to the ends of the floor (front, center, trunk) and/or pillar panel beating (front, center, rear) and/or car top panel beating and/or roof side rail panel beating and/or rear package tray panel beating.