A legally admissible and approved method in the city of chemically testing breath in order to detect or determine the presence of possible alcoholic intoxication shall be as follows:
(A) Breath samples of alveolar air shall be analyzed with an instrument specifically designed for the analysis of breath. The calculation of the blood alcohol concentration shall be on the basis of alveolar air to blood ration of 2100:1 and of mixed expired air to blood ration of 3200:1.
(B) The instrument to be used for analysis of alveolar air shall be the instrument commonly known and designated as the “breathalyzer.”
(C) (1) The Breathalyzer Model 1000 (distributor: Smith and Wesson Electronics Company, Eatontown, New Jersey) utilizes the chemical reaction illustrated by the following equation:
2Cr
2O72-+3CH3CH2OH+16H+ = 4Cr3+3CH3COOH+11H2O
(2) The alcohol in alveolar air is measured photometrically by the resulting color change from the yellow dichromate to the green of the chromium ions formed. This particular instrument is designed for quantitative breath alcohol determination.
(D) Breath-testing instruments must be calibrated no less frequently than after every 10 tests or after nine days if fewer than 10 tests are performed in any nine day period, using appropriate solutions of ethyl alcohol, and using methods and techniques for calibration recommended by the manufacturer of the calibration instrument.
(E) The operation or use of the “breathalyzer” shall be performed by a trained and qualified operator. The legal admissibility of the testimony of such operation shall be determined by the rules of admissibility of evidence as applied in courts of record of the state.
(F) The operator of the “breathalyzer” shall be paid a fee of $10 for each test performed.
('71 Code, § 509.05) (Ord. 236, passed 8-10-70; Am. Ord. 436, passed 12-8-75; Am. Ord. 783, passed 4-30-85)