TL;DR
OS/OW (Oversize/Overweight) regulations govern transport of loads exceeding standard dimensions or weight limits. Oversize typically means exceeding 8.5' width, 13.5-14' height, or 48-53' length. Overweight means exceeding 80,000 lbs GVW. Permits are required from each jurisdiction traveled.
OS/OW Regulations Guide
Understanding oversize and overweight (OS/OW) regulations is essential for anyone involved in heavy haul transportation. This guide covers the fundamentals of permit requirements, dimensional limits, weight restrictions, and compliance best practices.
What is an Oversize Load?
An oversize load is any shipment that exceeds the standard legal dimensions for traveling on public roadways. These limits vary by jurisdiction but generally include:
| Dimension | Typical US Limit | Notes |
|---|---|---|
| Width | 8.5 feet (102 inches) | Some states allow up to 8'6" without permit |
| Height | 13.5 - 14 feet | Varies significantly by state |
| Length (Trailer) | 48-53 feet | Combination limits also apply |
| Overall Length | 65-75 feet | Varies by road classification |
What is an Overweight Load?
An overweight load exceeds standard legal weight limits for axles or gross vehicle weight:
| Weight Type | Federal Limit (Interstate) |
|---|---|
| Gross Vehicle Weight (GVW) | 80,000 lbs |
| Single Axle | 20,000 lbs |
| Tandem Axle | 34,000 lbs |
| Bridge Formula | Varies by axle spacing |
Permit Requirements
Single-Trip Permits
Issued for a specific load moving from point A to point B on a defined route. Valid for a limited time (typically 5-10 days). Required information includes exact dimensions, weight, route, and vehicle configuration.
Annual/Blanket Permits
Cover multiple moves within a year up to specified dimension/weight limits. Cost-effective for carriers with regular OS/OW operations. Still require route-specific approval in some jurisdictions.
Superload Permits
Required for extremely large or heavy loads (typically exceeding 16' wide, 16' high, 150' long, or 200,000 lbs). Require detailed engineering analysis, route surveys, and often infrastructure modifications.
How to Get an OS/OW Permit
- Determine Load Dimensions - Measure and document exact height, width, length, and weight including trailer configuration.
- Plan Your Route - Identify origin, destination, and optimal path considering road conditions, bridges, and restrictions.
- Survey Constraints - Conduct route survey to identify potential obstacles like low bridges, narrow roads, and utility lines.
- Apply for Permits - Submit applications to each jurisdiction with load specifications and route details.
- Coordinate Escorts - Arrange required escort vehicles and law enforcement based on permit requirements.
- Execute Move - Complete transport following all permit conditions including travel times and approved route.
Frequently Asked Questions
What is an oversize load?
An oversize load exceeds standard legal dimensions for width (8.5'), height (13.5-14'), or length (48-53' trailer). These loads require special permits.
What is an overweight load?
An overweight load exceeds standard weight limits (80,000 lbs GVW federal limit, 20,000 lbs single axle, 34,000 lbs tandem axle). Permits are required.
Do I need permits for every state?
Yes, OS/OW permits are issued by individual states and provinces. Routes crossing multiple jurisdictions require a permit for each one.
What is bridge clearance?
Bridge clearance is the vertical distance from road surface to the lowest point of a bridge. Critical for oversize loads to avoid damage and safety hazards.
Simplify Your Permit Process
RoadScope helps you navigate multi-jurisdiction permit requirements with our built-in regulations database.
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