Brushing hair:<a href="#_ftn1" name="_ftnref1">[1]</a> It is permitted to comb and brush the hair during the Moed even though hair will be removed as a result. Doing so does not transgress sthe haircutting prohibition.
<a href="#_ftnref1" name="_ftn1">[1]</a> Rama 531:8; Mordechai Moed Katan

Shulchan Aruch HaRav | Brushing hair on Chol Hamoed

Brushing hair:[1] It is permitted to comb and brush the hair during the Moed even though hair will be removed as a result. Doing so does not transgress sthe haircutting prohibition. [1] Rama 531:8; Mordechai Moed Katan