I have a friend who is a christian and has dread hair, does the his dread hair invalidate my cloth for Solat?

All perfect praise be to Allaah, The Lord of the Worlds. I testify that there is none worthy of worship except Allaah, and that Muhammad is His slave and Messenger. We ask Allaah to exalt his mention as well as that of his family and all his companions.

We have already issued Fatwa 89389 clarifying that the impurity of a non-Muslim is abstract and it is not a corporeal impurity. If the body or hair of a non-Muslim touches a Muslim, the latter does not become impure, therefore, it is acceptable for you to perform the prayer with the clothes which were touched by the hair of the non-Muslim.

For more benefit about the limits of the relationship between a Muslim and a non-Muslim, please refer to Fatwa 88293.