Breathalyzers are delicate tools used for measuring alcohol in a person's breath. They require gentle handling to ensure proper functioning, and need to be cleaned periodically. Breathalyzers also need to be very accurate in their readings, and should be calibrated roughly once every six months. Proper cleaning and calibrating will provide precise readings every time.
Fill a spray bottle with hydrogen peroxide and spray a generous amount onto a soft cloth, dampening it.
Wipe the outside casing of the breathalyzer with a soft cloth, covering the front and back surface. Do this with ease, being careful not to damage or corrupt the delicate sensors. The hydrogen peroxide will clean and disinfect the breathalyzer of any dirt and germs. When finished, allow it to air dry.
Read the manufacturer's instruction manual on re-calibration. Some breathalyzers come with sensors that can be replaced by snapping out the used sensor and snapping in a new one. These sensors can be purchased online through the manufacturer's website. Models that don't have replaceable sensors need to be mailed in to the manufacturer's service center, where they use professional simulator systems for proper calibration. There are also stand-alone companies that calibrate breathalyzers. Conduct an online search for companies in the area who offer re-calibration services.
Never use rubbing alcohol to clean breathalyzers, as this will alter readings.