Guth Laboratories has developed precision, electronic simulators to calibrate and standardize preliminary and evidential breath analyzers used by law enforcement, the Department of Transportation, the National Review Board and educational institutions. The company manufactures the only simulator certified for use in hospitals and clinics. Guth also offers alcohol breath test accessories, supplies and service, including fuel cell sensors, sanitary mouthpieces and the smallest hand-carried preliminary breath tester. Guth Laboratories is located in Harrisburg, Pa.