South Dakota Cosmetology Practice Exam 2025 - Free Cosmetology Practice Questions and Study Guide

Determining the porosity of hair is most accurately achieved through conducting a strand test. A strand test involves taking a single strand of hair and observing how it reacts to moisture and products. This process helps in assessing how well the hair absorbs and retains moisture, which are key indicators of its porosity.

If the hair quickly absorbs moisture or products, it indicates high porosity, meaning that the cuticle layer is likely damaged or lifted, allowing for more moisture entry. Conversely, if the hair repels moisture initially, it suggests low porosity, indicating that the cuticle is tightly closed and prevents moisture from penetrating.

This method offers direct insights into the hair’s ability to interact with products, making it a practical approach for hairstylists to tailor their services based on an individual's hair needs. Other methods, while possibly informative, do not provide the same level of direct understanding of porosity as conducting a strand test does. Examining the hair texture or the cuticle layer alone may give some information about the overall condition of the hair but does not specifically measure porosity. Applying products to the hair may help in practical settings but does not provide a definitive measurement of porosity.