Infection Control, Sanitation, and Safety
Levels of control
Nearly every question in this domain turns on which level of control an item requires. Cleaning/sanitation physically removes debris and reduces microbial load; it is always the required first step before anything higher. Disinfection kills most pathogens (not spores) on nonporous surfaces using an EPA-registered, hospital-grade, tuberculocidal product. Sterilization destroys all microbial life including spores and is reserved for implements that penetrate skin or contact blood - autoclave, dry heat, or chemical sterilant.
Microbiology basics
Know the classes: bacteria (cocci, bacilli, spirilla), viruses (hepatitis B and C, HIV), fungi (the organisms behind ringworm and nail infections), and parasites. Pathogenic means disease-causing; contagious means spread person to person. Understand the chain of infection and where handwashing, PPE, and single-use items break it. Federal roles: OSHA enforces workplace safety and the Bloodborne Pathogens Standard, the EPA registers disinfectants, the FDA regulates devices and cosmetics. SDS sheets must be available for every chemical in the room.
Traps
Questions blur sanitize/disinfect/sterilize, or show an electrical tool being immersed (never - wipe with an EPA disinfectant). Implements must be scrubbed free of debris before soaking, or the disinfectant is inactivated by organic matter. UV cabinets are not sterilizers. Porous items - towels, sponges, cotton, wooden sticks - are single-use, not disinfectable.
Rule of thumb
Ask: does it contact blood or broken skin? Sterilize. Does it contact intact skin or is it a nonporous surface? Clean, then hospital-grade disinfect.