What protective feature does a mountaineering helmet have that a standard hardhat may lack?

A mountaineering helmet is specifically designed to offer protection against impacts from all angles, which is a crucial aspect when working in environments where falling objects or sudden impacts are possible from various directions. Unlike a standard hardhat, which typically provides protection primarily from vertical impacts, a mountaineering helmet has a more rounded shape and cushioning to absorb shocks from the sides, front, and back. This is particularly important in climbing and rope access work environments where the risk of falling rocks or equipment can occur from above as well as lateral impacts from swinging loads or contact with structures. As a result, the design and structural integrity of a mountaineering helmet ensure comprehensive protection, making it a crucial safety feature in high-risk situations.

In contrast, increased visibility, better ventilation, and flexible design for comfort, while important features in their own right, do not fundamentally address impact protection in the same comprehensive way that a mountaineering helmet does. The focus of the question is on the level of protection the helmet provides, which highlights the specific advantage of protection against impacts from multiple angles.