Defendant appeals her conviction by a jury for driving under the influence of intoxicants (DUII). ORS 813.010. She contends that the results of an Intoxilyzer test should have been suppressed because she regurgitated during the 15-minute pretest observation period. We affirm.
Tualatin Police Officer Manion arrested defendant for driving under the influence of intoxicants and brought her to the police station for an Intoxilyzer test. Before administering the test, Manion watched defendant for 15 minutes, as required by the administrative rules, and did not observe any signs that she had taken anything by mouth or regurgitated. He also completed a police department pretest checklist, which included an examination of defendant’s mouth. He did not, however, expressly ask her whether she had, in fact, regurgitated. She testified that she had inaudibly regurgitated during the 15-minute pretest observation period. The Intoxilyzer results indicated a .18 percent blood alcohol level.
Defendant moved to suppress the results of the Intox-ilyzer test, asserting that she had silently regurgitated shortly before the test was administered and that the fact that she did regurgitate compelled suppression pursuant to OAR 257-30-020(l)(b). That regulation reads:
“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.)
Defendant argued to the trial court that the regulation’s purpose is to insure the reliability of breath test results, which can be compromised by regurgitation. Consequently, she contended, regardless of the administering officer’s efforts to ‘ ‘make certain, ’ ’ the mere fact of regurgitation rendered the test results void and compelled their suppression.
The trial court denied defendant’s motion, concluding that, even assuming that defendant had regurgitated unbeknownst to the officer, the test results should not be suppressed because Manion had made an objectively reasonable effort to “make certain” that defendant had not regurgitated:
*534‘ ‘Defendant’s testimony that she, without any outward or perceptible sign, inadvertently brought ‘acid’ into her mouth, even if believed, does not render the test inadmissible. Her testimony may explain the test result and convince the jury that it does not help them determine her blood alcohol content at the time of driving as opposed to at the time of testing.
“The OAR requirement addresses the officer’s responsibility. He satisfied that. Using all human faculties, he made certain. The OAR does not require that the officer make inquiry. This officer had no evidence that would cause any lack of certainty.”
Defendant assigns the trial court’s ruling as error. She argues:
“An Oregon Administrative Rule requires that a breath test operator make certain that a person taking a breath test has not regurgitated liquid from the stomach into the mouth within fifteen minutes before taking the test. This defendant regurgitated liquid from her stomach into her mouth in the fifteen minutes before taking the test. Because violation of the administrative rule effected [sic] the scientific accuracy of the breath test, the evidence was improperly admitted.”
The issue before us is whether the trial court erred in concluding that the rule was satisfied. Consequently, we must decide what OAR 257-30-020(l)(b) requires. The pertinent language of the rule provides that the operator “must make certain” that the subject has not taken anything by mouth, vomited or regurgitated for at least 15 minutes before taking the test.
We must first consider the text and context of the rule. The dissent concludes that the language of “the rule focuses on the objective truth”; whether, in fact, the subject has taken anything by mouth, vomited or regurgitated during the 15-minute pre-test observation period. However, that is not what the rule provides. Rather, the language of the rule focuses on the conduct of the officer. Under the rule, the officer is directed to take certain actions to ensure that the breath test is properly performed. Although the dissent’s recitation of the meaning of the term “certain” is accurate, that word cannot be considered in a vacuum. It must be read together with the other words of the rule, which direct the conduct of the person administering the test.
*535The language of the rule must also be read consistently with its context. OAR 257-30-020(l)(b) was adopted pursuant to ORS 813.300 and ORS 813.160(l)(b). ORS 813.300 authorizes the use of blood alcohol percentages as evidence in a DUII case. ORS 813.160(l)(b) provides that to be valid under ORS 813.300, chemical analyses of a person’s breath shall be performed according to methods approved by the state police. OAR 257-30-020(l)(b) was adopted by the Oregon State police to carry out that responsibility. Accordingly, it is clear that the rule’s purpose is to provide the methodology designed to assure that breath test results are accurate. However, there is nothing in the language of the statutes or the rule that provides that the methodology must guarantee that the test results are completely accurate.
Under the dissent’s view, evidence that the procedures required by the rule have been followed may be irrelevant. As the dissent reads the rule, any evidence that a subject vomited, regurgitated or took something by mouth, if believed by the court, would be completely determinative of compliance with the rule and, consequently, admissibility,1 regardless of the particular circumstances. Essentially, the dissent reads'the rule to require that the pretest procedures guarantee that the Intoxilyzer tests are completely accurate. Under that reading of the rule, even if all of the procedures required by the rule have been completely satisfied, if 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 a matter of law, to *536conclude that the rule was not complied with and that the results of the Intoxilyzer test were inadmissible.
We conclude that the pertinent inquiry in ascertaining whether the rule has been complied with is whether the observing officer has followed the precautions required by the rule. If so, the rule is satisfied and the evidence of the test results is admissible. Accordingly, evidence that a subject did, in fact, take something by mouth, or regurgitated during the observation period, does not automatically mean that the rule was not satisfied. However, such evidence is not irrelevant. This evidence may be pertinent to whether the procedures of the rule really were followed. For example, if the evidence shows that the subject did take something by mouth or regurgitated during the observation period and that an examiner would have observed these events if following the proper procedures, such evidence would be pertinent to the court’s decision as to whether the rule’s procedures were followed. For instance, if a subject testifies that he or she loudly and visibly vomited during the observation period, and the court believes that testimony, this could be the basis of the court’s determination that the pretest procedures were not complied with.
There is, however, no such evidence here. The trial court concluded that Manion used “all human faculties” to make certain that the defendant did not take anything by mouth, vomit or regurgitate liquid from her stomach to her mouth and that, accordingly, the rule was satisfied. The trial court’s determination is supported by the evidence and is consistent with the language of the rule.
Defendant argues and the dissent agrees that its understanding of the rule is compelled by our prior case law. We disagree. Defendant first relies on State v. Hanson, 19 Or App 498, 528 P2d 100 (1974), for the proposition that as a result of what occurred here, the test result is “void” and is not “valid” under ORS 813.300. In Hanson, the defendant moved to suppress the results of a breathalyzer test on the ground that the officer who was performing the test had failed to “make certain” that the defendant had not regurgitated within the 15-minute observation period as required by an administrative rule (OAR ch 333) promulgated under former ORS 483.644(1), the predecessor to ORS 813.160(l)(b). The *537officer administering the test testified that he did not see the defendant drink, smoke, eat, take medication, vomit or regurgitate liquid during the pertinent time. On cross-examination the officer conceded that the defendant had coughed just before taking the test. The defendant produced no evidence. The trial court excluded the test result from the evidence on the ground that the rule was not complied with. We reversed on the basis that the administrative rule referred to discharges from the stomach into the mouth and did not require the operator of the test to make certain that the defendant had not coughed and that the officers adequately observed the defendant.
The language from Hanson, on which defendant particularly relies, is that:
“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[.]” Hanson, 19 Or App at 503. (Emphasis omitted; emphasis supplied.)
As the concurrence correctly notes, the above language is dicta. Further, it simply explains that the procedures in the rule were “designed to assure” that an uncontaminated sample is obtained and that failure to follow the procedures will void the result. Nowhere in Hanson did we say that the procedures must absolutely guarantee thát a suspect does not take anything by mouth, vomit or regurgitate and, if a defendant proves that he or she did any of those things during the observation period, it follows, as a matter of law, that the rule was not satisfied.
Our understanding of Hanson is confirmed by our holding in a later case, State v. Lessar, 105 Or App 512, 805 P2d 730, rev den 311 Or 482 (1991). In that case, the defendant challenged the admission of the Intoxilyzer test on the basis that OAR 257-30-020(l)(b) was not satisfied. The defendant relied on the officer’s testimony that, although he had *538observed the defendant for 15 minutes and was “quite certain” that he did not vomit or regurgitate, he was not certain that the defendant did not put anything in his mouth. The defendant argued that the officer’s uncertainty required the conclusion that the requirement of the rule that the examiner “make certain” that nothing was taken by mouth was not met. We concluded:
“The threshold issue is whether the state has presented a prima facie case. The trial court found that the trooper was quite certain that defendant did not vomit or regurgitate during the pertinent 15 minute period. It also found that the trooper had ‘observed the defendant in a reasonable manner’ and had not observed defendant place anything in his mouth. We agree with the trial court that absolute certainty is not required by OAR 257-30-020(l)(b) and that the trooper’s testimony established aprima facie case. In the light of the fact that defendant did not present any evidence that he had regurgitated, vomited or taken anything by mouth while he was in the patrol car and during the eight-block ride to the Harney County Sheriffs office, the trial court correctly denied defendant’s motion.” Id. at 517. (Footnote omitted.)
The dissent here ignores the language from Lessor that, despite the requirement that the observing officer “make certain” that a subject has not vomited, regurgitated or taken anything by mouth, that “absolute certainty” is not required by the rule. Instead, it reads our decision in Lessor and our decision in State v. Demings, 116 Or App 394, 841 P2d 660 (1992), rev den 315 Or 443 (1993), as supporting its view that the rule imposes an objective standard. Specifically, the dissent relies on the language quoted above, from Lessor, that
“In the light of the fact that defendant did not present any evidence that he had regurgitated, vomited or taken anything by mouth * * * the trial court correctly denied defendant’s motion.” Lessor, 105 Or App at 517.
The dissent also points to similar language in Demings. In Demings, the observing officer testified that he was not aware of the need to look for regurgitation in the sense of the defendant’s having regurgitated liquid from his stomach to his mouth. He did state that he observed the defendant for 30 minutes and that he did not see him take anything by mouth, vomit or regurgitate. The trial court *539found that this established a prima facie case of compliance with the rule and we agreed. We said:
“It was then incumbent on defendant to place facts in the record which, if true, would demonstrate that official duty in administering the test was not regularly done. State v. Lessar, supra, 105 at 515. Defendant offered no evidence that he had regurgitated.” Demings, 116 Or App at 397.
The dissent reads this language in Lessar and Demings to mean that if evidence that the defendant had, in fact, taken something by mouth, vomited or regurgitated during the observation period was introduced, that would automatically overcome evidence that the observing officer did properly perform the pretest requirements of the rule. Although we did note that the defendants in those cases presented no such evidence and, therefore, the state’s prima facie showing of compliance was not overcome, we did not say that such evidence would automatically have overcome the state’s evidence of compliance. As discussed above, that will depend on the specific evidence offered. Evidence that shows that a person following the procedures of the rule would have observed the vomiting, etc., could overcome the state’s showing of compliance with the rule. However, evidence, such as that presented here, that the regurgitation was silent, was not otherwise noticeable and was not communicated to the observing officer, does not preclude the conclusion that the pretest procedures were complied with.
The trial court here found that the officer correctly administered the Intoxilyzer, complied with all requirements of the administrative rules governing the use of the Intoxilyzer, and, in particular, “made certain” that defendant had not regurgitated any liquid. The evidence supports these findings and, under our reading of OAR 257-30-020(l)(b), the trial court properly concluded that the rule was satisfied. The trial court did not err in denying the motion to suppress.
Affirmed.
The concurrence would hold that compliance with the administrative rule is not determinative of the admissibility of the Intoxilyzer test results in a judicial proceeding. First, we do not believe it is appropriate to address this issue as it was not argued by the parties. Further, the holding suggested by the concurrence would be inconsistent with our existing case law. State v. McVay, 83 Or App 312, 731 P2d 466 (1987). See State v. Demings, 116 Or App 394, 841 P2d 660 (1992), rev den 315 Or 443 (1993); State v. Herring, 112 Or App 83, 827 P2d 932 (1992); State v. Lessar, 105 Or App 512, 805 P2d 730, rev den 311 Or 482 (1991); Gildroy v. MVD, 100 Or App 538, 540, 786 P2d 757 (1990), aff'd 315 Or 617, 848 P2d 96 (1993); State v. Leach, 94 Or App 778, 767 P2d 463 (1989); State v. Goddard, 87 Or App 130, 741 P2d 540 (1987); State v. Allen, 74 Or App 275, 702 P2d 1118, rev den 300 Or 111 (1985); State v. McClary, 59 Or App 553, 557, 651 P2d 145 (1982); State v. Kacalek, 34 Or App 967, 580 P2d 205 (1978); State v. Hanson, 19 Or App 498, 501-02, 528 P2d 100 (1974). Finally, contrary to the concurrence’s assertions, its holding is not required by State v. O’Key, 321 Or 285, 899 P2d 663 (1995), because, in this case, the legislature has delegated the appropriate authority to the agency. ORS 813.300(1); ORS 813.160(l)(b).