Given that general cargo securement requires a WLL of at least 50% of cargo weight, how many 1/2-inch Grade 70 chains would be required for a load of 34,500 lbs?

To determine the number of 1/2-inch Grade 70 chains required for a load of 34,500 lbs, we need to calculate the minimum Working Load Limit (WLL) required based on the weight of the cargo:

WLL = 50% of cargo weight
= 0.5 x 34,500 lbs
= 17,250 lbs

Next, we need to find the WLL rating of a single 1/2-inch Grade 70 chain. According to the National Association of Chain Manufacturers (NACM) standards, the WLL rating of a 1/2-inch Grade 70 chain is 11,300 lbs.

Finally, we can calculate the number of chains required:

Number of chains = (Total weight of cargo) / (WLL rating of a single chain)
= 34,500 lbs / 11,300 lbs
= 3.05

Since we cannot use a fractional number of chains, we would need to use at least 4 chains to secure the cargo.