FHWA's 13-Class Vehicle Classification: A Complete Breakdown
When it comes to traffic data collection and transportation planning in the United States, the Federal Highway Administration (FHWA) has set the gold standard with its 13-Class Vehicle Classification System. This comprehensive vehicle categorization is a critical tool for agencies and traffic survey companies to analyze road usage patterns, plan infrastructure, and manage traffic efficiently.
What is the FHWA 13-Class System?
The FHWA 13-Class System is a standardized method used to classify vehicles based on their axle count and vehicle type. It provides consistency across traffic data studies, ensuring that data from different locations and studies are comparable.
The classification includes everything from motorcycles and passenger cars to multi-unit trucks and buses. Each class is defined by a specific vehicle configuration, making it a valuable asset for accurate and detailed traffic studies.
FHWA Vehicle Classes Overview
Here’s a simplified breakdown of each of the 13 FHWA vehicle classes:
Class 1 – Motorcycles: Two or three-wheeled motorized vehicles.
Class 2 – Passenger Cars: Includes sedans, coupes, and station wagons.
Class 3 – Other Two-Axle, Four-Tire Vehicles: Pickup trucks, SUVs, vans.
Class 4 – Buses: All buses, including school and transit buses.
Class 5 – Two-Axle, Six-Tire Single Units: Larger delivery trucks.
Class 6 – Three-Axle Single Units: Medium-duty trucks with 3 axles.
Class 7 – Four or More Axle Single Units: Large single-unit trucks.
Class 8 – Four or Less Axle Single-Trailer Trucks: Smaller semi-trucks.
Class 9 – Five-Axle Single-Trailer Trucks: Most common tractor-trailers.
Class 10 – Six or More Axle Single-Trailer Trucks
Class 11 – Five or Less Axle Multi-Trailer Trucks
Class 12 – Six-Axle Multi-Trailer Trucks
Class 13 – Seven or More Axle Multi-Trailer Trucks
Each class offers granular insight into the vehicle types using road networks, which is critical for pavement design, road safety planning, and environmental impact analysis.
Why the FHWA Classification Matters
Consistency Across States & Regions: Enables cross-comparison of data nationwide.
Detailed Data Granularity: Supports traffic engineers in distinguishing between different levels of wear and tear vehicles cause.
Helps with Funding & Policy Decisions: Accurate counts per vehicle class can influence state funding and infrastructure investments.
Supports Weight & Toll Analysis: Especially for truck-heavy corridors.
Application in Real-World Traffic Studies
FHWA classification is widely applied in:
Vehicle classification counts
Weigh-in-motion (WIM) systems
Turning movement counts with classification
Traffic impact assessments for highway projects
At Traffic Data Count, we specialize in capturing highly accurate vehicle classification data using both manual and automated methods. Whether it’s for short-term surveys or long-term infrastructure planning, our experienced team ensures that vehicle classes are identified and recorded with precision.
How Traffic Data Count Ensures Accuracy
Trained staff for manual classification
High-resolution video footage analysis
Use of AI-assisted recognition tools
Adherence to FHWA and local standards
We understand that accuracy in classification leads to better decisions for city planning and safer roadways.
Conclusion
FHWA’s 13-Class Vehicle Classification System provides the backbone for traffic data collection in the U.S. By categorizing vehicles with such specificity, traffic engineers, planners, and government bodies can rely on a standardized system for effective traffic management.
If your project requires detailed vehicle classification or you’re planning to conduct a traffic impact study, reach out to our team at Traffic Data Count. Let’s ensure your data drives meaningful outcomes.
