What system is used by colorists to assess the lightness or darkness of hair color?

The level system is the appropriate method used by colorists to assess the lightness or darkness of hair color. This system is based on a numerical scale that typically ranges from 1 to 10, where 1 represents the darkest black and 10 indicates the lightest blonde. By utilizing this standardized scale, colorists can accurately categorize hair colors and communicate specific shades more effectively.

This system is essential for creating consistent results in hair coloring services, as it provides a clear reference point for both stylists and clients. The level system helps professionals understand how various hair colors can be lifted or toned, guiding them in selecting the right color formulations to achieve the desired results.

Other options are less applicable in this context. For instance, shade guides may provide a visual reference for specific hair colors but do not offer a systematic way to measure lightness or darkness. The color spectrum includes a broad range of colors but does not specifically segment hair color levels. The intensity scale pertains more to the vibrancy or saturation of color rather than the lightness or darkness of the base shade. Thus, using the level system is the most effective way for colorists to assess hair color accurately.