Texas Cosmetology Operator Written ExamHair Care ServicesHard
A cosmetologist is performing a hair coloring service on a client who previously used a metallic dye. To prevent a severe chemical reaction when applying an oxidative hair color, what test should the cosmetologist perform first?
- AStrand test
- BMetallic salt test
- CPatch test (predisposition test)
- DPorosity test
Show answer & explanationAnswer & explanation
Correct answer: B. Metallic salt test
Metallic dyes can react violently with oxidative hair colors (which contain peroxide), causing extreme heat, breakage, and scalp irritation. A metallic salt test is specifically designed to detect the presence of these metallic salts before proceeding with oxidative color.
Why the other options are wrong
- A. A strand test checks for color processing and integrity, not specifically for metallic dye interaction.
- C. A patch test checks for allergic reactions, not chemical reactions with metallic dyes.
- D. A porosity test assesses the hair's ability to absorb moisture, not the presence of metallic dyes.
Metallic Salt Test
A test performed on a client's hair strand to detect the presence of metallic salts (from metallic dyes), which can cause severe chemical reactions, extreme heat, and damage when mixed with oxidative hair colors (containing peroxide).
- Detects metallic dyes (e.g., lead, silver, copper)
- Prevents adverse chemical reactions with oxidative colors
- Involves immersing a hair strand in a specific solution (e.g., 1 oz 20 volume peroxide + 20 drops 28% ammonia)
- Color change or heat indicates metallic salts
- If positive, oxidative color should not be applied
Memory trick: Metallic 'M' calls for a 'M'etallic test.