This part of ISO 24415 specifes requirements and test methods for the durability of tips for crutches, and is not applicable to tips manufactured for special purposes. The requirements and test method are based on tips being used with an ordinary gait on dry and fat walking surfaces.Crutches include elbow crutches, forearm support crutches, and axillary crutches, as described in ISO 9999.NOTE Special purposes might include walking on ice and/or snow.