Which aspect is NOT part of the general hours of a hairdressing course?

In the context of a hairdressing course, the curriculum typically focuses on skills and techniques directly related to hair services. Shampooing, haircutting, and manicuring are essential components of a hairdressing program, as they involve practical applications of hair care, styling, and nail services that are crucial for a cosmetologist's skill set.

Skin assessment, however, is generally associated with esthetics and skin care rather than hairdressing. While there may be some intersection between hair care and skin knowledge, a specific emphasis on skin assessment is not a primary focus of a hairdressing course. Therefore, this aspect does not align with the core competencies required for hairdressing training, making it the correct choice for what is not included in the general hours of study for hairdressing.