How Many Ratchet Straps Do You Need?

To determine how many ratchet straps you need, you must know some key information about what you are trying to secure. Weight and length of the cargo are crucial in determining the number of straps needed. Also critical is the working load limit of your strap assembly.

Working Load Limit (WLL) is the maximum load a component or assembly should be subjected to during routine use. These values apply to new products in normal working conditions and are marked by the manufacturer on the synthetic web tie down assembly or other cargo securement system.

U.S. Department of Transportation regulations subchapter B-Motor Carrier Safety Regulations, 49 CFR, Part 393, Paragraph 393.102(b) requires that: "The aggregate working load limit of the tie down assemblies used to secure an article against movement in any direction must be at least 1/2 times the weight of that article."

Example of Working Load Limit and Determining Tie Downs Needed

  1. Weight of article being secured is 24,000 LB
  2. Working Load Limit of the synthetic web tie down is 3,333 LB
  3. Required aggregate Working Load Limit is: 1/2 x 24,000 LB = 12,000 LB
  4. Minimum number of tie downs: 12,000 LB / 3,333 LB = 4 tie downs

Truck With Four Tie Downs

In the above example only the weight of the object is in consideration. Other factors also determine the number and location of tie downs.

Blocked or Not

If an article of cargo is not blocked:

  • 1 ratchet strap is needed for articles 5 ft or less in length, and 1,100 lbs or less in weight
  • 2 ratchet straps are needed if the article is 5 ft or less in length and more than 1,100 lbs OR the article is greater than 5 ft but less than 10 ft, regardless of weight
  • If the item is longer than 10 ft, 2 ratchet straps are required for the first 10 ft with 1 additional strap for every 10 ft or fraction of, beyond the first 10 ft

If an article of cargo is blocked or positioned to prevent forward movement:

  • 1 ratchet strap is needed for every 10 ft of length or fraction thereof