What is the difference between Rated Capacity and Working Load Limit (WLL)?

• A. Rated Capacity is the maximum load for a configuration per the manufacturer; WLL is the safe working limit used in field charts; use the lower value.
• B. WLL is higher than Rated Capacity.
• C. Rated Capacity is calculated by field charts; WLL is theoretical.
• D. They are the same.

Answer: (A)

The key idea is understanding what each term represents and how they’re used in practice. Rated Capacity is the maximum load the equipment is designed to carry for a specific configuration, as defined by the manufacturer. The Working Load Limit (WLL) is the safe working limit used in field charts for actual lifts, reflecting safety factors and real-use considerations.

In practice you must use the lower value when planning or performing a lift. The WLL is the practical, safety-focused limit you should not exceed in the field, and it already accounts for factors like rigging geometry, equipment condition, and dynamic forces. The Rated Capacity is a theoretical maximum for the configuration, but it may not reflect safe operation under real conditions. Therefore, the correct approach is to take the lower of the two.

The other statements aren’t correct because the WLL is not necessarily higher than the Rated Capacity, Rated Capacity isn’t calculated by field charts, and they are not always the same.