Definition and purpose
Vehicle classification groups observed road users using client-approved decision rules. A useful scheme states what qualifies for each class, how uncertain cases are handled and whether classification is body-type or axle-based.
Use it when volume totals need a meaningful split for planning, freight, design or operational analysis.
Required inputs
- Client or authority class scheme
- Definitions and decision rules
- Location and observation periods
- Source suitability review
- Output columns and aggregation rules
Video and camera considerations
Footage must make the visual cues required by the scheme observable. Camera angle, distance, occlusion and night conditions can prevent reliable distinction between similar classes.
Observation, classification and intervals
Observation process
Apply the same definition at each location and time interval. Maintain an exception log for classes that cannot be established from the available evidence.
Movement and classification process
Do not substitute a generic country scheme for the approved project scheme. Motorcycle, scooter, car, SUV, pickup, van, LCV, bus, minibus, coach and heavy-vehicle splits should be specified where relevant.
Time intervals
Classes are recorded within the selected traffic interval so totals can be reconciled to all-vehicle counts.
Validation and QA/QC
Check class totals against overall volume, re-review a sample of ambiguous conditions and test that category labels are used consistently across outputs.
Common problems and limitations
- Side-on imagery can hide axle configuration.
- Vehicle overlap can conceal a body type.
- Unwritten class definitions lead to analyst drift.
Classification is limited by what the source material can show; exact axle configurations may need a different collection method.
Typical deliverables
- Classified interval tables
- Class dictionary and notes
- Exception treatment where applicable
- QA summary
Illustrative output format
Illustrative sample data only — not a project result or benchmark.
| Interval | Passenger car | LCV | Bus | Heavy vehicle |
|---|---|---|---|---|
| Illustrative 15 min | 82 | 7 | 3 | 5 |
Frequently asked questions
Is a passenger car the same as an SUV?
Only if the agreed class scheme treats them that way.
Can classes differ by country?
Yes. Use the client-approved or locally required scheme and document it.