Chemistry, Product Knowledge, and Implements
Products and their properties
Know the classes: solvents (acetone, polish remover), adhesives (resin, cyanoacrylate), monomer/polymer systems, UV gels, and disinfectants. Understand pH, acids/alkalis, and that all salon chemicals should be stored labeled, closed, and away from heat and flame. Acetone is flammable and volatile; ventilate.
Implements
Classify tools by material and use. Metal implements (pushers, nippers, cuticle scissors) can be disinfected and sterilized. Porous items (wooden sticks, emery boards, buffer blocks, cotton) are single-use. Nonporous items like plastic or glass can be disinfected per label. Implements should be cleaned of debris before immersion in disinfectant, and stored in a clean covered container.
Traps
Questions test which implements can be reused and how. A common trap is assuming a file can be disinfected; it cannot. Another is mixing disinfectant strengths or skipping the cleaning step. Also know that product contamination (double-dipping, dirty brushes) spreads microbes.
Rule of thumb
Metal = disinfect/sterilize; porous = discard; nonporous = disinfect. Never double-dip, and always clean before you disinfect.