Is human hair pure (tahir) or impure (najis), whether attached or detached?

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Human hair is pure, both when attached to the body and when detached, both during the person's life and after their death. The evidence for this is that the Prophet, peace be upon him, divided his hair among his companions after shaving. Anas narrated that the Prophet gave the right side of his hair to the barber to shave, then gave it to Abu Talha al-Ansari, and then gave the left side to him to shave, giving that to Abu Talha as well, commanding him to distribute it among the people (Narrated by Muslim and Abu Dawud). Furthermore, Muawiyah willed that a portion of the Prophet's hair be placed in his mouth upon his death, and Khalid possessed a cap containing hairs from the Prophet's hair. If it were impure, these actions would not be permissible, nor would the Prophet have distributed it while knowing they would take it for blessing (*tabarruk*). Whatever was pure from the Prophet was pure from others like it. Also, since attached hair is pure, detached hair is pure, similar to the hair of all animals. We also state this regarding human limbs, but even conceding impurity for limbs, they only become impure upon separation during life, unlike hair.