Which of the following can cause equipment-related problems while diving?

Using unfamiliar equipment can indeed lead to equipment-related problems while diving. When divers utilize gear they are not familiar with, they may not fully understand how to operate it correctly or recognize its specific features and limitations. This lack of familiarity increases the risk of malfunction or misuse, which can compromise diver safety. For instance, a diver might struggle to manage buoyancy control with a new buoyancy compensator or might misinterpret gauge readings, leading to critical errors underwater.

Other factors listed, such as not using top-of-the-line equipment, can influence performance but aren’t as directly related to the immediate understanding and operational awareness demanded by unfamiliar gear. Proper inspection and maintenance are critical for equipment reliability, but even well-maintained gear can pose problems if a diver does not know how to use it effectively. Similarly, equipment fit is crucial for comfort and function, yet the primary concern with using unfamiliar equipment is the risk stemming from a lack of knowledge and experience with its specific operation and features.