Oregon Revised Statutes Oregon Vehicle Code § 813.300

(1) At the trial of any civil or criminal action, suit or proceeding arising out of the acts committed by a person driving a motor vehicle while under the influence of intoxicants, if the amount of alcohol in the person's blood at the time alleged is less than 0.08 percent by weight of alcohol as shown by chemical analysis of the person's breath or blood, it is indirect evidence that may be used with other evidence, if any, to determine whether or not the person was then under the influence of intoxicants.

(2) Not less than 0.08 percent by weight of alcohol in a person's blood constitutes being under the influence of intoxicating liquor.

(3) Notwithstanding subsection (2) of this section, for purposes of the Motorist Implied Consent Law as defined in ORS 801.010, for a person who is under 21 years of age, any amount of alcohol in the blood constitutes being under the influence of intoxicating liquor.

(4) Percent by weight of alcohol in the blood shall be based upon grams of alcohol per 100 milliliters of blood or based upon grams of alcohol per 210 liters of breath.