Cargo Securement Rules: FMCSR Part 393 Explained

Why Cargo Securement Matters

Improperly secured cargo is one of the leading causes of preventable crashes and roadside violations for commercial motor vehicles. The FMCSA cargo securement rules, codified in 49 CFR Part 393, Subparts I and J, establish the minimum standards for securing articles of cargo on or within commercial motor vehicles operating in interstate commerce. These rules protect not only the driver but also other motorists and roadside workers.

General Securement Requirements

Under 49 CFR 393.100, all cargo must be firmly immobilized or secured on or within the vehicle by structures of adequate strength, dunnage, shoring bars, tiedowns, or a combination of these methods. The cargo securement system must be capable of withstanding the following forces:

• Forward: 0.8 times the weight of the cargo (80% of cargo weight)
• Rearward: 0.5 times the weight of the cargo (50% of cargo weight)
• Sideways: 0.5 times the weight of the cargo (50% of cargo weight)
• Upward: 0.2 times the weight of the cargo (20% of cargo weight)

These performance criteria ensure that cargo remains stable during normal driving maneuvers including braking, turning, and evasive actions.

Tiedowns and Working Load Limits

A tiedown is any device used to secure cargo, including chains, straps, wire rope, and cordage. Each tiedown must have a working load limit (WLL) marked by the manufacturer. The aggregate WLL of all tiedowns securing an article must equal at least 50% of the weight of the article.

Minimum Number of Tiedowns

The number of tiedowns required depends on the length and weight of the cargo:

1. Articles 5 feet or shorter and weighing 1,100 lbs or less require at least one tiedown
2. Articles 5 feet or shorter and weighing more than 1,100 lbs require at least two tiedowns
3. Articles longer than 5 feet but 10 feet or shorter require at least two tiedowns
4. For articles longer than 10 feet, one additional tiedown is required for each additional 10 feet or fraction thereof

Commodity-Specific Rules

Subpart J of Part 393 provides additional securement rules for specific types of cargo that present unique challenges. These commodity-specific sections include:

• Logs (393.116) -- requirements for securing logs transported on flatbeds and log trailers
• Dressed lumber and building products (393.118) -- bundled lumber, plywood, and similar materials
• Metal coils (393.120) -- specific tiedown configurations based on coil orientation
• Paper rolls (393.122) -- vertical and horizontal positioning requirements
• Concrete pipe (393.124) -- blocking and bracing for pipe loads
• Intermodal containers (393.126) -- chassis securement standards
• Automobiles, light trucks, and vans (393.128) -- minimum number of tiedowns per vehicle transported
• Heavy vehicles, equipment, and machinery (393.130) -- preparation and restraint of oversized equipment
• Flattened or crushed vehicles (393.132) -- securing baled or crushed auto bodies
• Roll-on/roll-off containers (393.134) -- front and rear restraint systems

Inspection and Enforcement

During roadside inspections, law enforcement officers evaluate cargo securement as part of both Level I and Level II inspections. Common violations include insufficient tiedowns, damaged straps or chains, and cargo shifting. These violations carry significant weight in the FMCSA Safety Measurement System and can result in out-of-service orders if the cargo presents an imminent hazard.

Use TruckCodes to look up the specific securement violation codes and understand how they affect your carrier profile.