Updated 2026-11-01
Open-deck loads stay put only if they are tied down correctly. Federal cargo securement rules for commercial motor vehicles are in 49 CFR Part 393, Subpart I. This guide covers the basic ideas; read the rules and FMCSA's driver handbook on cargo securement for details.
Working load limits
Every tiedown has a working load limit, or WLL, which is the most it should carry in use. The federal rules require the combined working load limit of all tiedowns securing an article to be at least half the article's weight. Use tiedowns marked with their WLL, and do not rely on unmarked chain or straps.
Number of tiedowns
The minimum number of tiedowns depends on the length and weight of the article, and whether it is blocked against forward movement. Longer and heavier items need more. Some commodities, such as heavy machinery and vehicles, have specific rules of their own.
Equipment and machinery
Heavy equipment commonly requires chains at the front and rear, with attachments and accessories lowered and secured. Check the commodity-specific rules for equipment above certain weights.
Inspect on the road
Drivers generally must inspect cargo and securement devices before the trip and within the first 50 miles, then again at intervals during the trip, such as at duty changes or after set periods of driving. Tighten anything that has loosened.
Damaged gear
Replace straps with cuts, chains with stretched or cracked links and binders that do not hold. Damaged tiedowns can fail suddenly and may not count toward the required working load limit.
Why it matters for insurance
A load that falls off can injure others and damage the freight. Cargo policies may exclude damage caused by improper securement, and roadside violations show up on your safety record. Good securement protects your coverage and your reputation.