dissenting.
“Make certain” means make certain. It does not mean, as the majority would have it, “make a reasonable effort.” Accordingly, I dissent.
I agree with the majority that violations of OAR 257-30-020(l)(b) necessitate the suppression of breath tests.1 We differ, however, as to what constitutes compliance with that rule. Although the majority concludes that the administering officer’s conformance to certain pretest procedures is sufficient, that result cannot be squared with the rule’s plain language and purpose. Rather, the “make certain” requirement of OAR 257-30-020(l)(b) compels suppression of breath test results whenever a suspect has actually regurgitated, compromising the objective integrity of the breath sample.
OAR 257-30-020(l)(b) provides:
“Pre-test Requirement. The operator must make certain the subject has not taken anything by mouth, (drinking, smoking, eating, taking medication, etc.) vomited, or regurgitated liquid from his stomach into his mouth, for at least 15 minutes before taking the test[.]” (Emphasis supplied.)
Our decisions of late have properly cautioned against rote reliance on dictionary definitions. See, e.g., State v. Holloway, 138 Or App 260, 265, 908 P2d 324 (1995). Nevertheless, this is one case in which plain meaning, by reference to dictionaries or otherwise, is irresistible. “Certain” means “established beyond doubt or question,”2 “established as true or sure,”3 “not to be doubted as a fact,”4 and “marked by complete assurance and conviction, lack of doubt, reservation, suspicion, or wavering.”5 Moreover, the rule states that *548the operator “must make certain” that the subject has not regurgitated, not that the operator “be certain.” Thus, the rule focuses on the objective truth, the certainty, of a particular fact — whether the subject has taken anything by mouth, vomited, or regurgitated dining the 15-minute pretest period — and not on the subjective reasonableness of the operator’s belief or conduct.
That focus bespeaks the rule’s purpose: to assure that Intoxilyzer results are based on “clean” breath samples. To be “valid” for purposes of ORS 813.160,6 and thus admissible under ORS 813.300,7 a chemical analysis of a suspect’s breath must be performed according to methods approved by the Department of State Police. Thus, OAR 257-30-020(l)(b) was promulgated to ensure the validity of test results:
“Failure to ‘make certain’ that a suspect does not put anything into his mouth, vomit or regurgitate liquid from his stomach for the required 15 minutes will void the results of the breath analysis because any of those acts may introduce into the mouth traces of alcohol which will contaminate the ‘alveolar’ (lung) air which breathalyzer equipment is designed to gauge. The approved methods set out by the Health Division in OAR ch 333 are designed to assure an uncontaminated breath sample; both vomiting — discharge from the stomach through the mouth — and regurgitation of *549liquids from the stomach into the mouth are likely to result in the presence of residual mouth alcohol which will cause the test results to show an artificially high percentage of alcohol.” State v. Hanson, 19 Or App 498, 503, 528 P2d 100 (1974) (emphasis in original).
Consistent with that purpose, our cases have held that the state’s proof of compliance with various pretest observation procedures can support a presumption that a defendant did not regurgitate during the pretest period and that the test results were thus uncontaminated. Compare State v. Demings, 116 Or App 394, 397, 841 P2d 660 (1992), rev den 315 Or 443 (1993) (affirming denial of suppression motion where state, by evidence of operator’s observation, established prima facie case of regulatory compliance and defendant “offered no evidence that he had regurgitated”); and State v. Lessar, 105 Or App 512, 517, 805 P2d 730, rev den 311 Or 482 (1991) (same) with State v. McVay, 83 Or App 312, 731 P2d 466 (1987) (affirming suppression of Intoxilyzer results where operator delegated part of testing procedure to third party and failed to inquire whether the defendant had vomited or regurgitated). Nevertheless, if the rule’s plain language and its fundamental “uncontaminated sample” purpose are to be given effect, the state’s prima facie showing of compliance can, and must, be overcome by credible evidence of actual regurgitation. If the trial court finds that a suspect actually regurgitated during the pretest period, the Intoxilyzer result must be suppressed.
The majority implies that so applying and enforcing OAR 257-30-020(l)(b) would encourage subterfuge and hamstring law enforcement:
“[I]f a subject manages to regurgitate without the observing officer knowing it and later manages to convince the court that this occurred, the court would be required, as matter of law, to conclude that the rule was not complied with and that the results of the Intoxilyzer test were inadmissible.” 138 Or App at 535-36.
Those fears are misplaced for at least two reasons. First, before being entitled to suppression, defendants must first convince trial judges that, notwithstanding an officer’s adherence to pretest observation procedures, regurgitation did, *550in fact, occur. Thus, trial courts’ credibility determinations will effectively screen baseless claims of undetected regurgitation.
Second, and in a related sense, officers administering Intoxilyzer tests can engage in observation practices that will buttress the state’s prima facie showing of compliance. For example, after completing the pretest observation, and before taking the breath sample, the operator can ask whether the subject regurgitated dining the observation period. If the response is negative, it will obviously be more difficult for the subject/defendant to credibly claim later that he or she actually regurgitated. Such a procedure is neither unusual nor unworkable. Indeed, Officer Manion indicated that he routinely followed that practice, but inexplicably failed to do so in this case. There is no slippery slope here.
OAR 257-30-020(l)(b) is clear: The operator must make certain that the subject has not regurgitated during the pretest period. If defendant did, in fact, regurgitate, Manion necessarily did not make certain of the converse, and the Intoxilyzer results must be suppressed. Because the trial court did not render a finding as to whether defendant actually regurgitated during the 15-minute pretest period,8 the judgment should be vacated and the case remanded for appropriate findings.9
*551I respectfully dissent.
Riggs, De Muniz, and Armstrong, JJ., join in this dissenting opinion.The concurrence espouses a qualitatively different analysis. However, I agree with the majority, 138 Or App at 535 n 1, that that analysis is inapposite.
American Heritage Dictionary of English Language 220 (1979).
Random House College Dictionary 229 (1973).
Webster’s Third New International Dictionary 367 (Unabridged 1993).
Id.
ORS 813.160 reads, in part:
“(1) To be valid under ORS 813.300:
* * * *
“(b) Chemical analyses of a person’s breath shall be performed by an individual possessing a valid permit to perform such analyses issued by the Department of State Police and shall be performed according to methods approved by the Department of State Police. For the purposes of this paragraph, the Department of State Police shall do all of the following:
“(A) Approve methods of performing chemical analyses of a person’s breath.
“(B) Prepare manuals and conduct courses throughout the state for the training of police officers in chemical analyses of a person’s breathf.]”
ORS 813.300 provides, in part:
“(1) At the trial of any [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 .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.”
Defendant contends that the trial court found that she regurgitated during the pretest period. She points particularly to the court’s remarks during the suppression hearing:
“And your argument is * * * that if you have a historical fact that she did, in fact, regurgitate some material ■— and I am prepared to make that finding; I find her believable — that it’s not admissible * *
However, in its order denying defendant’s suppression motion, the court did not render such a finding. Instead, the court stated, “defendant’s testimony * * * even if believed does not render the test inadmissible.” (Emphasis supplied.) When a written judgment varies from a prior oral ruling, the written judgment controls. See State v. Swain/Goldsmith, 267 Or 527, 530, 517 P2d 684 (1974). Thus the trial court did not render a finding as to whether defendant actually regurgitated during the 15-minute pretest period.
The state contends that, regardless of whether defendant actually regurgitated, any error in failing to suppress the Intoxilyzer results was harmless because there was “little, if any likelihood” that the admission of that evidence affected the jury’s verdict. State v. Walton, 311 Or 223, 231, 809 P2d 81 (1991). The record, however, is to the contrary; the breathalyzer test results were central to the prosecution’s case.