Certified med techs usually work in laboratories, often in rotating shifts. Their duties might include matching blood types to prepare a patient for a transfusion or analyzing a patient's bodily fluids to look for bacteria or other microorganisms. Other tests certified med techs are trained to perform include urinalysis, comprehensive metabolic panels (CMP) and complete blood count (CBC). These tests help doctors diagnose and treat patients, as well as verifying the efficacy of applied treatments. Though they may work with infectious specimens, certified med techs take safety precautions and wear protective gear to minimize hazards.