Pierron, J.:
Kelly K. Rhodes appeals her conviction of driving while intoxicated (DUI). She argues the police DUI checkpoint was unconstitutional and, as a result, her conviction should be reversed. She also argues the Intoxilyzer 8000 test results should have been suppressed because the officers failed to comply with the Kansas Department of Health and Environment (KDHE) regulations and the Intoxilyzer 8000 was not properly certified. We affirm.
On August 22, 2008, Overland Park Police set up a DUI checkpoint along Metcalf Avenue. Motorists were directed off Metcalf Avenue and into a parking lot where they were directed into enforcement lanes. The enforcement lane officers had been instructed to look for signs of alcohol consumption or impaired drivers. If they noticed impairment or consumption, the officers asked the driver to step out of tire vehicle and undergo further testing. If an individual was asked to undergo additional testing, another officer would park the vehicle and any passengers would wait in the waiting area.
Rhodes was directed into the enforcement lane in front of Officer Christopher Moore. He smelled the odor of alcohol coming from the Rhodes vehicle and noticed that her eyes were red, watery, and bloodshot. Officer Moore told Rhodes that the operation was a DUI check point and asked her if she had been drinking that night. With slurred speech, Rhodes admitted she had been drinking. Officer Moore asked Rhodes to perform field sobriety tests. He had her perform the HGN, the walk and turn, and one-leg stand, and recite the alphabet and some numbers. Rhodes exhibited several clues of impairment. As a result, Officer Moore arrested Rhodes for DUI and escorted her to the booking area.
At 1:04 a.m., Officer Moore checked Rhodes’ mouth for any foreign objects. He read her the Miranda rights, gave her a written copy of the DC-70, and read the implied consent advisories to her. Rhodes agreed to take a breath test. Between 1:04 a.m. and execution of the breath test, Officer Moore kept Rhodes in constant observation to make sure she did not put any foreign objects into [59]*59her mouth. Twenty minutes later, Officer Moore walked Rhodes over to a van where Deputy Hamilton performed the breath test. Rhodes blew a .115 alcohol concentration on the breath test. Rhodes was arrested and charged with DUI.
On June 18,2008, Rhodes was found guilty of DUI in municipal court and sentenced to 180 days in jail. Her conviction was affirmed by the district court.
For her first argument on appeal, Rhodes argues the majority of the factors under State v. Deskins, 234 Kan. 529, 673 P.2d 1174 (1983), weigh in favor of the suppression of the evidence and, thus, because the State failed to prove the reasonableness of the checkpoint stop under the Fourth Amendment to the United States Constitution, the district court ex'red in failing to suppress the results of the stop.
“An appellate court reviews the district court’s decision on a motion to suppress using a bifurcated standard. Without reweighing the evidence, the district court’s findings are reviewed to determine whether they are supported by substantial competent evidence. The appellate court then reviews the ultimate legal conclusion regarding the suppression of evidence using a de novo standard.” State v. Woolverton, 284 Kan. 59, 70, 159 P.3d 985 (2007).
The Fourth Amendment protects individuals against “ ‘ “arbitrary invasions by government officials” by imposing a standard of reasonableness upon the exercise of those officials’ discretion.’ ” State v. Barker, 252 Kan. 949, 953, 850 P.2d 885 (1993). Stopping and detaining a motorist without some “ ‘articulable and reasonable suspicion’ ” of unlawful conduct is an unreasonable seizure under the Fourth Amendment. 252 Kan. at 953. However, checkpoint cases have carved out an exception to this general rule. 252 Kan. at 953.
In order to meet this exception, these cases have set out a series of factors that must be weighed together in determining the constitutionality of a DUI checkpoint. They are as follows:
“Numerous conditions and factors must be considered in determining whether a DUI roadblock meets the balancing test in favor of the [State]. Among the factors which should be considered are: (1) The degree of discretion, if any, left to the officer in the field; (2) the location designated for the roadblock; (3) the time and duration of the roadblock; (4) standards set by superior officers; (5) advance notice [60]*60to the public at large; (6) advance warning to the individual approaching motorist; (7) maintenance of safety conditions; (8) degree of fear or anxiety generated by the mode of operation; (9) average length of time each motorist is detained; (10) physical factors surrounding the location, type and method of operation; (11) the availability of less intrusive methods for combating the problem; (12) the degree of effectiveness of the procedure; and (13) any other relevant circumstances which might bear upon the test. Not all of the factors need to be favorable to the State but all which are applicable to a given roadblock should be considered.” Deskins, 234 Kan. at 541.
Thus, the court must weigh each of these factors, recognizing that “[n]ot all of the factors must be favorable to die State.” Barker, 252 Kan. at 953. Following is an analysis of each of the Deskins factors in the context of the present case:
The Degree of Discretion, If Any, Left to the Officer in the Field
The kind of standardless and unconstrained discretion that results from an officer s ability to stop any vehicle out of whim “ ‘is the evil the Court has discerned when ... it has insisted that the discretion of the official in the field be circumscribed, at least to some extent.’ ” Deskins, 234 Kan. at 535. “ ‘To that end, the Fourth Amendment requires . . . that [a] seizure must be carried out pursuant to a plan embodying explicit, neutral limitations on the conduct of individual officers.’ ” 234 Kan. at 536. As part of this plan, “ ‘ “questioning all oncoming traffic at roadblock type stops is one possible alternative.” ’ ” 234 Kan. at 539.
In this case, the officers had no discretion regarding which cars to stop, they were to stop all vehicles. The officers in charge set up strict standards for the officers to follow and provided a briefing on these standards to each officer before they went on duty at the checkpoint. The officers were even given standard greetings to give to each driver and told to hand drivers a brochure and inquire whether the driver had anything to chink drat evening. From die facts, there was little, if any, degree of discretion left to die officers performing the DUI checkpoint.
The Location Designated for the Checkpoint
Rhodes introduces persuasive authority that “statistics concerning the extent of the problejn of drunk driving” should be pre[61]*61sented. This does not necessarily make the checkpoint unreasonable however. The location chosen by the officers was because of the high DUI and alcohol incidents in the area and because a severe fatality had recently occurred nearby. In support of this reasoning, the State produced evidence of the area being a “high accident” area. Although no specific “statistics” were presented, in an area that is already a high accident area, it would be reasonable for the officers to set up a DUI checkpoint to lessen the further possibility of more accidents being caused by the accident-prone drunk driver.
The Time and Duration of the Checkpoint
Several cases have considered DUI checkpoints that started late at night, typically between 10 p.m. and 2 a.m. In each of these cases, the checkpoint was held to be constitutional. See, e.g., Davis v. Kansas Dept. of Revenue, 252 Kan. 224, Syl. ¶ 1, 843 P.2d 260 (1992); Deskins, 234 Kan. at 531, 542-43. Similarly, the DUI checkpoint in this case was operated from 11 p.m. to 2 a.m.
Standards Set by Superior Officers
In Barker, 252 Kan. at 956, the court concluded that briefing the officers prior to operating the checkpoint was sufficient to meet this standard. In its reasoning, this briefing period, performed by an officer’s superiors, was sufficient to instruct officers on the expectations and procedures for the checkpoint. 252 Kan. at 956. Here, Officer Koos, the officer in charge of the checkpoint, provided two briefing sessions: one for the set-up staff and one for officers arriving later. This process was to assure that all officers attended at least one briefing. In preparation for the briefings, Officer Koos put together handouts and a PowerPoint presentation. Clearly, the officers had uniform operating standards established by their superior officers.
Advance Notice to the Public at Large
In both Barker and State v. Jackson, 24 Kan. App. 2d 38, 40, 942 P.2d 640, rev. denied 262 Kan. 965 (1997), the court was not concerned about the absence of advance warning to the public. The Barker court held that although desirable, “its absence does [62]*62not by itself vitiate the checklane.” 252 Kan. at 956. On July 31, 2008, Officer Koos received a forwarded email regarding the DUI checkpoint that was addressed to several different media outlets. Although there was no evidence that the checkpoint was advertised through these media oudets, this is not enough to “vitiate the checklane.” See Barker, 252 Kan. at 956.
Advance Warning to the Motorist Approaching the Checkpoint
The Barker court recognized that warning signs posted approximately 500 feet before cars entered the checkpoint lane was adequate advance notice. 252 Kan. at 956. Here, not only did the officers place a “DUI Checklane Ahead” sign 500 feet before entering the checkpoint, they also had “Be prepared to Stop” signs posted before that. According to Barker, these measures were sufficient to give advance warning to individual approaching motorists.
Maintenance of Safety Conditions
Officer Koos testified she took the officers’ safety into consideration in planning for the checkpoint. She made sure the area was well lit, level, and adequate advance notice had been posted so the vehicles would not be dangerous to the officers. She also made sure the officers wore appropriate traffic vests and carried flashlights. Officers set up cones directing traffic. Officers were placed at each turn to direct the cars through the cones into the enforcement lanes. Through traffic signage, the officers tried to control the traffic flow to prevent cars from running into each other. The parldng lot, where the actual checkpoint was set up, was deemed safer than the roadway. Just as in Barker, “great pains were taken by the State to insure the safety of all travelers, as well as the officers in the operation.” 252 Kan. at 956.
Degree of Fear or Anxiety Generated hy the Mode of Operation
“The anxiety factor in Deskins does not speak in terms of hypothetical anxiety. The Deskins factor is phrased Tear and anxiety generated.’ ” State v. MacDonald, 253 Kan. 320, 323, 856 P.2d 116 (1993). The record is silent regarding actual fear or anxiety generated by the checkpoint. But it can be assumed that “other vehicles [were] being stopped, [so they could] see visible signs of the [63]*63officers’ authority, and [would be] much less likely to be frightened Michigan Dept. of State Police v. Sitz, 496 U.S. 444, 453, 110 S. Ct. 2481, 110 L. Ed. 2d 412 (1990). Thus, without affirmative evidence in the record, the presumption is that any concern or anxiety that may have existed dissipated when a motorist saw the traffic signs, police officers, and other traffic control devices.
Average Length of Time Each Motorist is Detained
“The essence of the Fourth Amendment prohibition is to safeguard the privacy and security of individuals against arbitrary invasions by governmental officials by imposing a standard of reasonableness upon the exercise of those officials’ discretion.” Deskins, 234 Kan. at 540. Thus, in balancing governmental interests against the resulting intrusion on the individual, reasonableness is the key. See 234 Kan. at 540-41.
In Sitz, the United States Supreme Court found that a 25-second delay for each vehicle was not sufficient to violate constitutional standards. Likewise, in Davis die delay time was roughly 31 seconds, and in Barker the delay amounted to about 45 seconds. In each of these cases, the court found that the delay to the motorist was constitutionally permissible and reasonable. Specifically, the Barker court took into account the purpose for which detainment occurred and recognized that in some situations a longer detainment would be necessary. 252 Kan. at 957. The court concluded that, overall, the “officers complied with their initial plan of detaining motorists momentarily.” 252 Kan. at 957. Even though the delay was longer in this case, it does not amount to being unreasonable.
During the operation of the 4-hour checkpoint in this case, 601 vehicles went through. The police department reported that the average length of the stop was 147 seconds. The officers determined this average by randomly timing 14 vehicles as they made their way through the checkpoint. Not only were the officers checking for intoxicated drivers, they were also distributing brochures about the purpose of the checkpoint, the effects of DUIs, and trying to educate the public as a whole. In balancing the government’s interest with the intrusion on an individual, it would appear, [64]*64taken in its totality, the 147-second detainment was a reasonable amount of time to carry out the checkpoint’s purposes.
Physical Factors Surrounding the Location, Type, and Method of Operation
The Deskins court looked to the fact that there were 35 to 40 officers involved in the checkpoint, it was set up in a well-lit area, there were red flashing lights, officers were uniformed, and tire location was chosen by supervisory personnel. As in Deskins, the police department here performed briefings, set out cones with officers directing traffic into the enforcement lane, the area was well lit, and tire officers had flashlights and wore appropriate traffic vests. Furthermore, supervisors — not the officers in the field— chose the area to locate the checkpoint.
Rhodes argues that the checkpoint in question had no permanency and, therefore, does not meet this factor. This misinterprets Deskins. The Deskins court ruled the checkpoint constitutional without taking into account the permanency of the location. See 234 Kan. at 546 (Prager, J., dissenting). We agree with Deskins that the permanency of the location is not the appropriate consideration for this factor.
The Availability of Less Intrusive Methods for Combating the Problem
It would appear this factor is wrapped up with the effectiveness factor as we look to whether the goal of the checkpoint was accomplished and effective. See Barker, 252 Kan. at 957. Rhodes argues there were other less intrusive ways to prevent DUIs. like putting the officers at the exit of a bar to explain the consequences of DUI or to advertise through the radio. Similarly, Officer Koos admits there were less intrusive alternatives. In support of Rhodes’ argument, she introduces persuasive authority noting that “[njothing in the record indicates that the only practical or effective means of apprehending drunk drivers” is through a DUI checkpoint. Officer Koos testified that if education was the only purpose of the checkpoint, advertising on the radio or television would be less intrusive.
[65]*65However, in considering less intrusive methods, not every conceivable alternative to DUI prevention must be considered. If that were the case, a DUI checkpoint would never be permissible because there would always be a less intrusive way to prevent drunk driving — increase the penalty. Rather, a court looks to see if the goals of the checkpoint were accomplished and effective. See Barker, 252 Kan. at 957. The State recognized the checkpoint could have been done better and the results were probably not worth it. Even with this recognition however, the checkpoint is not unconstitutional. The checkpoint was still extremely effective in educating the public and, arguably, in getting drunk drivers off the road.
The Degree of Effectiveness of the Procedure
In Deskins, 2,000 to 3,000 cars were stopped and only 15 persons arrested for DUI. In Davis, 255 motorists were stopped and 7 DUI arrests were made. And in Sitz, 126 vehicles passed through the checkpoint and only 2 drivers were arrested for DUI. From tírese cases, it is clear that effectiveness is not measured solely as a percentage of cars stopped to arrests made. Rather, it must be judged in accordance with the original goal. Here, 601 vehicles passed through the checkpoint and 10 DUI arrests were made. Following precedent, it would appear that a 1.6% arrest rate is more than sufficient for the effectiveness factor. Additionally, 601 drivers were educated on the effects of DUIs, an impact with 100% effectiveness. That achieved one of the police department’s purposes.
Any Other Relevant Circumstances Which Might Bear Upon the Test
All relevant circumstances have been considered above, and Rhodes does not present any other factor that should be weighed in the analysis.
In balancing the Deskins factors together to weigh the State’s interest in operating the checkpoint with the intrusion on the individual, we conclude the police department appropriately considered and carried out the majority of the Deskins factors in the [66]*66operation of its DUI checkpoint on August 22, 2008. It was, therefore, constitutional, and the district court did not err in failing to suppress the results of the stop.
For her second argument on appeal, Rhodes argues the district court erred in
denying her motion to suppress the Intoxilyzer 8000 test results. She asserts the court erred because the “City failed to establish that the police ‘substantially complied’ with KDHE protocol.” We disagree.
“[T]his court reviews the factual underpinning of a district court’s decision for substantial competent evidence and the ultimate legal conclusion drawn from those facts de novo. The ultimate determination of the suppression of evidence is a legal question requiring independent appellate review. [Citation omitted.]” State v. Moore, 283 Kan. 344, 349, 154 P.3d 1 (2007).
Rhodes also argues there was an inadequate evidentiaiy foundation for the Intoxilyzer test results. We review this question as a question of fact, and “it is reviewed for substantial competent evidence supporting the district court’s finding.” State v. Rivera, 42 Kan. App. 2d 914, 922, 218 P.3d 457 (2009), rev. denied 290 Kan. 1102 (2010). “So long as there is substantial competent evidence to support the finding, it will not be disturbed on appeal.” State v. Lieurance, 14 Kan. App. 2d 87, 91, 782 P.2d 1246 (1989), rev. denied 246 Kan. 769 (1990).
In order for the State to introduce the results of a breath test, it “must lay a foundation showing that the testing machine was operated according to the manufacturer’s operational manual and any regulations by [KDHE].” Lieurance, 14 Kan. App. 2d at 91. In Mitchell v. Kansas Dept. of Revenue, 41 Kan. App. 2d 114, 123, 200 P.3d 496, rev. denied 289 Kan. 1279 (2009), the court stated: “If affirmative evidence that a breath[-alcohol test] sample was not contaminated is presented . . . , this is a factor the court may consider in deciding whether substantial compliance with the [breath testing] protocol has been satisfied.”
Here, Detective Moore testified he was so close to Rhodes he would have noticed if she had vomited, belched, or regurgitated during the 20-minute deprivation period. He did not hear or see [67]*67any burp or regurgitation. This is affirmative evidence that the breath test was not contaminated and, therefore, Detective Moore substantially complied with the KDHE breath-testing protocol.
The State also must present evidence that the testing equipment was certified by the KDHE. See Lieurance, 14 Kan. App. 2d at 91-93. Here, the evidence clearly showed the instrument and operator were certified. Rhodes is not contending there was a certificate in place for the testing equipment. Instead, she argues the “Johnson County Sheriff s Office did not have a certificate for breath-testing issued by the [KDHE] that evidenced the machine was certified pursuant to the administrative regulations in place on and after March 14, 2008.”
This issue has recently been resolved by the Kansas Supreme Court in State v. Ernesti, 291 Kan. 54, Syl. ¶ 7, 239 P.3d 40 (2010). The Emesti court was faced with a similar situation involving an Intoxilyzer 8000. The court recounted a brief history of the statutory evolution because, as here, the issue centered on the validity of the certification for an Intoxilyzer that was issued before the statutory changes occurred, and the testing was completed before, under the new statutory regime, recertification occurred. See 291 Kan. at 57-58. The court rejected Emesti’s argument that the breath test results should be suppressed because the certificate had not been certified under the new regulations. See 291 Kan. at 64-69. In the end, the Emesti court concluded: “There is no requirement . . . that the testing device be certified under regulations in effect on the date of testing; rather, the device must simply be certified.” 291 Kan. at 70. We are bound to follow precedent, and thus, we conclude that because the testing equipment was certified, although not under the new regulations at the time of testing Rhodes, it still substantially complied with KDHE regulations.
Affirmed.
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