The State, pursuant to § 547.200(1), RSMo Supp.1984, appeals from an order suppressing the results of a Breathalyzer test. Reversed and remanded.
Kurt Marquart, a State Highway Patrol Trooper, arrested Wyssman on January 8, 1984, after he observed Wyssman driving on the shoulder of 1-70. The trooper stopped Wyssman and observed indications of intoxication. He gave Wyssman a field sobriety test and had Wyssman get in the patrol car so that he could take him to the Blue Springs Police Department.
Riding with Trooper Marquart was his brother, Kyle, pursuant to permission given by the trooper’s superior officer.
After Wyssman had entered the patrol car, the trooper noticed another vehicle entering 1-70 from an exit ramp. The trooper got out of his car to stop the other car, and was thus out of sight of Wyssman for about one minute. Kyle remained in the car and observed Wyssman while the trooper was gone.
After the trooper re-entered his car, he drove Wyssman to the Blue Springs Police Department. The trooper, who was certified to operate the machine, used the Alco-Analyzer Model 2000 to give Wyssman a breath test. The result of the breath test was a reading of .139.
Section 577.026, RSMo Supp.1984, states that the breath test shall be administered in accordance with the rules of the Department of Health. The Department of Health has adopted a regulation, 13 C.S.R. 50-140.060(10), which provides that in using the Alco-Analyzer Model 2000, the subject is to be observed “for at least fifteen (15) minutes — no smoking or oral intake of any material during this time; if vomiting occurs, start again with the fifteen (15) minute observation period.”
Wyssman moved to suppress the results of the breath test because the test was not performed according to the prescribed procedures. He contended that because only 15 minutes and 39 seconds had elapsed from the time the trooper first observed Wyssman until he administered the test, subtracting the one minute the trooper was out of his car left an observation time of only 14 minutes and 39 seconds. Wyssman further contended that the observation by the trooper’s brother could not be utilized to fill the gap in the trooper’s observation. The trial court sustained Wyssman’s motion to suppress the results of the breath test.
On this appeal, the parties agree as to the facts relating to the time involved and to the presence of the trooper’s brother in the patrol car. At oral argument Wyss-man’s counsel agreed that the trooper’s brother would testify that Wyssman did not smoke or take anything into his mouth or vomit while the trooper was away from the car for the one minute.
The question to be resolved is whether an officer must himself physically observe the person to whom the breath test is to be administered for the entire 15 minute period, or if someone else may participate in the observation to supply the required 15 minutes. No Missouri case has considered this question but the same situation was addressed in Wester v. State, 528 P.2d 1179 (Alaska 1974), cert. denied, 423 U.S. 836, 96 S.Ct. 60, 46 L.Ed.2d 54 (1975). In Wes-ter the court considered a requirement essentially identical to the Missouri regulation. There, the tester was required to observe the subject for at least 15 minutes to insure that he did not regurgitate or place anything in his mouth during that time. In Wester the observation was made by the arresting officer and not by the officer conducting the test. The court held that although the testing officer did not personally observe Wester, he was under adequate observation by the arresting offi*848cer for a sufficient period of time. Id. at 1184-85[4]. The court further noted, “The mere assertion that ingestion was hypothetically possible ought not to vitiate the observation period foundational fact so as to render the breathalyzer test results inadmissible.” Id. at 1185.
In this case there is no contention that Wyssman smoked or took anything into his mouth or vomited during the 15 minutes prior to the test. Rather, the contention is that the arresting officer, who performed the test, did not physically observe Wyss-man for the entire 15 minutes. This court agrees with the holding in Wester and finds that there is sufficient evidence in the record to determine that Wyssman was observed for a period of 15 minutes, and that he did not do any of the things mentioned in the rule during this period which would be likely to produce a false reading on the breath machine. The parties agree that the trooper’s brother would testify that nothing occurred while the trooper was out of the car, and except for that one minute, the evidence is sufficient to find that the trooper observed Wyssman for 15 minutes prior to the test. In Wester the court noted that courts should not indulge in the hypothetical exercise that a person may have done one of the acts mentioned in the rule which would affect the test results. In order to defeat the test on that ground, it is necessary that evidence be adduced that one of the acts contemplated by the rule occurred.
While State v. Hanson, 19 Or.App. 498, 528 P.2d 100 (1974), does not precisely involve the same question, the court held that there was sufficient compliance with an observation rule — similar to the one in this case — even though the officer had his back to the defendant for about one minute. Also, in State v. Steele, 52 Ohio St.2d 187, 370 N.E.2d 740 (1977), the court held that the 20 minute observation period was not broken during the time an officer left his vehicle and walked around it to let the defendant out on the other side. The court in Steele relied on Wester and found its reasoning to be highly persuasive. Obviously the court in these cases found the lapse in observation to be so short as to be insignificant. The thrust of these cases is that the officer’s observation need not be shown to exist for every moment of the required time so long as the record is sufficient to give adequate assurance that the person observed did not do something covered by the rule which would skew the test result. Here the lapse in observation is covered by the observation of the trooper’s brother which makes this a stronger case than Hanson and Steele.
The only reason advanced as to why the observation must be made by a person certified to operate the breath machine is that someone else will not know the things they are to observe. Certainly it does not require an expert to observe whether or not a person has smoked a cigarette or placed anything in his mouth or vomited. The only purpose of the rule is to assure that none of these things have occurred. When the record demonstrates that assurance then the purpose of the rule has been fulfilled. To require a literal 15 minute unbroken observation by a single officer who is certified to operate the machine is to place form over substance.
Here, the record demonstrates that Wyssman was observed during the 15 minutes prior to the test, and that nothing mentioned in the rule occurred to cause the result of the test to be flawed. The court erred in suppressing the test results. The order suppressing the results is reversed and this cause is remanded for further proceedings.
SHANGLER, J., concurs.
MANFORD, J., dissents in separate opinion.