Question 54 OSV02 - Mate - Offshore Supply Vessels

The Correct Answer is A ### Explanation for Option A (Lashings are always required) When securing containers using **non-locking fittings** (such as stacking cones or manual twistlocks that are not engaged), the intermediate connection between the containers provides little to no resistance against lifting, horizontal sliding, or tipping forces. Standard cargo securing practice and international guidelines (like the IMO CSS Code) require that stacks secured only by non-locking fittings must be reinforced by external lashings or fixed structures (like cell guides) to ensure stability, **even in a two-high stack** (i.e., when the tier is one container high). If the fittings do not lock, the entire stability of the stack relies on the lashings. Therefore, lashings are required regardless of the height of the stack, starting immediately when the stack is built. *** ### Explanation of Why Options B, C, and D are Incorrect * **B) One container:** This implies lashings are only required when the stack exceeds one container (i.e., starting at three high). This is incorrect. If non-locking fittings are used, the stack must be secured by lashings the moment the second container is placed. Waiting until the stack exceeds one container high leaves the two-high stack unsecured against lifting and tipping. * **C) Two containers / D) Three containers:** These heights (implying three-high or four-high stacks, respectively) represent typical thresholds where lashings are required *when using automatic locking twistlocks*. Since the problem specifies **non-locking fittings**, the stack is inherently unstable and unsecured at much lower heights. Waiting until three or four containers high would violate mandatory securing rules and create a high risk of cargo failure, even in normal weather.