Washington Esthetician State Board Practice Exam 2026 – Complete Prep Resource

Infrared light is known for its ability to penetrate the deepest layers of the skin compared to the other types of light listed. It operates at a wavelength that allows it to reach underlying tissues, potentially stimulating circulation, reducing inflammation, and promoting healing. This deep penetration makes infrared light particularly effective for therapeutic purposes, such as pain relief and tissue repair.

Visible light, while useful for various skin treatments, does not penetrate as deeply. It primarily affects the outer layers of the skin and has a more limited effect when it comes to deeper skin conditions. Ultraviolet light, while capable of affecting specific skin conditions, primarily targets the epidermis and can carry risks such as skin damage and increased sun sensitivity. LED light therapy utilizes different wavelengths aimed at varying skin concerns, but its penetration is generally not as deep as that of infrared light.

Thus, infrared light's unique properties and deep penetration make it the most effective choice for certain therapeutic applications in esthetic treatments.