Virgin thio relaxers may be applied after all of the following procedures except:

Virgin thio relaxers can be applied after various procedures, but not after a vigorous shampoo. A vigorous shampoo may strip the hair's natural oils and disrupt its protective barrier, potentially increasing the risk of chemical damage when applying a relaxer. When performing a virgin thio relaxer, it's important that the hair is in a healthy state to minimize the risk of over-processing or damage.

A light shampoo is acceptable as it helps to remove any surface impurities without overly affecting the hair's natural protective oils. An analysis of the hair and scalp is essential for determining the overall health of the hair and scalp before proceeding with chemical services. Additionally, performing a strand test and an elasticity test is crucial to assess the hair's condition and ability to withstand the chemical processes involved in relaxation. These practices help ensure the hair is ready for the application of the relaxer, whereas a vigorous shampoo could inadvertently compromise the hair’s integrity before the treatment.