How can you determine if the hair is in a healthy condition before a treatment?

Conducting a strand test is an effective method to determine the condition of the hair before a treatment. This technique involves taking a small section of hair and applying the intended treatment to assess how the hair reacts. It helps in evaluating the hair's strength, elasticity, and overall health, allowing the cosmetologist to make informed decisions regarding further treatments. This is crucial because it ensures that any chemical or heat application won't cause additional damage to already compromised hair.

Assessing color, checking the scalp, or evaluating hair length does not provide specific insights into the hair's internal structure or its integrity. While these factors can contribute to an overall impression of hair quality, they do not give detailed information about the hair’s ability to withstand various treatments, making the strand test the most comprehensive approach to assessing hair health.