(1) "Accuracy" means the proximity of a measured value to a reference value.

(2) "Alcohol" means the unique chemical compound ethyl alcohol.

(3) "Blank test" means the testing of an instrument to ensure that no alcohol from a previous test can interfere with a person's breath test.

(4) "Concentration" means the weight amount of alcohol, expressed in grams, contained in two hundred ten liters of breath or alcohol/water vapor.

(5) "Data entry" means the process of providing information to the instrument for the purposes of identifying a breath test document to an individual.

(6) "Interference" means a test result whose infrared absorbance or electrochemical analysis properties are not consistent with ethyl alcohol.

(7) "End expiratory air" means the last portion of breath to be delivered to the instrument once the appropriate sample acceptance criteria have been met.

(8) "External standard test" means the process by which the accuracy of the instrument is verified, using a simulator containing a certified simulator solution or a compressed gas standard containing a known alcohol concentration.

(9) "Internal standard test" means the process by which the instrument calibration is verified.

(10) "Precision" means the ability of a technique to perform a measurement in a reproducible manner.

(11) "Simulator" means a device which when filled with a certified simulator solution, maintained at a known temperature, provides a vapor sample of known alcohol concentration.

(12) "Valid breath sample" means a sample of a person's breath provided in such a manner to be accepted for analysis by the instrument.