Clean climbing

Clean climbing is a rock climbing term that describes techniques and equipment which climbers use in order to avoid damage to the rock. These techniques date at least in part from the 1920s and earlier in England, but the term itself may have emerged in about 1970 during the widespread and rapid adoption in the United States and Canada of nuts (also called chocks), and the very similar but often larger hexes, in preference to pitons, which damage rock and are more difficult and time-consuming to install. Pitons were thus eliminated in North America as a primary means of climbing protection in a period of less than three years.

Due to major improvements in equipment and technique, the term clean climbing has come to occupy a far less central, and somewhat different, position in discussions of climbing technology, compared with that of the brief and formative period when it emerged four decades ago.

Drilled and hammered equipment such as bolts, pitons, copperheads and others scar rock permanently. Various protection devices became widely available around 1970, which were far less likely to damage rock and much faster and easier to install, when used sensibly. Such "clean" gear, as of contemporary times, now include spring-loaded camming devices, nuts and chocks, and slings, for hitching natural features.

Contemporary alternatives to pitons, which used to be called "clean climbing gear", have made most routes safer and easier to protect, and have greatly contributed to a remarkable increase in the standards of difficulty notable since about 1970. Pitons are now regarded as highly specialized equipment, needed by a small minority of climbers interested in routes of peculiar difficulty.

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