OPINION
BILL MEIER, Justice.I. Introduction
Appellant Stephanie Lynn Bekendam appeals her conviction for driving while intoxicated, felony repetition.1 In one issue, Bekendam contends that the trial court erred by allowing the State’s expert to testify to trace levels of cocaine that the expert found when analyzing a sample of Bekendam’s blood. We will affirm.
II. Background
The underlying facts of this case are largely undisputed. The record demonstrates that on February 28, 2008, a witness saw Bekendam driving erratically, colliding her SUV into parked vehicles, and jumping curbs. Bekendam eventually ran a red light and struck another vehicle, injuring its driver and passenger. Emergency medics took Bekendam, the driver of the other vehicle, and its passenger to the hospital. While at the hospital, because an EMT and an attending nurse reported that Bekendam’s breath smelled of alcohol, the police procured a sample of Bekendam’s blood.
After the blood was tested and determined to contain no alcohol, the State or*360dered the blood tested for any controlled substances or dangerous drugs. Beken-dam does not contest that she operated a motor vehicle in a public place, nor does she contest that she had previously been convicted of two prior charges of driving while intoxicated (DWI). The dispute in this case is whether the trial court erred by allowing the State’s expert witness to testify to having found trace levels of cocaine in Bekendam’s blood that, according to the State’s expert, demonstrates that Bekendam had cocaine in her system both at the time of the blood draw and at the time she ran the red light. Prior to expert testimony at trial, the trial court conducted a Daubert/Kelly hearing2 outside the presence of the jury to determine whether it would allow the expert to testify to what she had found when analyzing Bekendam’s blood.
At the hearing, Renee Hawkins, the State’s expert witness who analyzed Bek-endam’s blood sample, testified that she is a forensic scientist with the Texas Department of Public Safety Crime Laboratory’s toxicology section. She testified that she is trained in the analysis of biological specimens for alcohol and drugs. She is a member of the Southwestern Association of Toxicologists and of the International Association of Chemical Testing. Hawkins explained to the trial court that the department has a procedure in which it first tests blood samples for several classes of drugs and then, if any of those classes of drugs are detected and per department policy, a second, additional, confirmation test is conducted to confirm the type of drug and the amount of that drug contained in the sample. Hawkins said that both of these tests are generally accepted within the scientific community and that the results of these tests had been admitted in evidence by courts throughout Texas and the United States. Hawkins testified that she tested Bekendam’s blood sample. According to Hawkins, Beken-dam’s blood tested positive for cocaine3 *361using the first test, “enzyme-multiplied immunoassay technique,” otherwise known as “EMIT.”4 Hawkins said that she confirmed the results using “the Gas Chro-matograph/Mass Spectrometer or [GCMS].” According to Hawkins, under GCMS, Bekendam’s blood contained traces of both cocaine and a metabolite, benzoy-lecgonine, which can only enter the bloodstream via the consumption of cocaine. After explaining cocaine’s half-life and the level of benzoylecgonine found in Beken-dam’s blood sample, Hawkins testified that there may have been significant amounts of cocaine in Bekendam’s blood at the time she ran the red light and collided with the other vehicle.
Hawkins testified that she did not include cocaine as a drug detected in Beken-dam’s blood on her toxicology report because the results under the GCMS test were “under the .05 [reportable] cutoff point, .05 is our limit for cocaine.” When asked directly why she would testify that Bekendam’s blood contained cocaine when her report did not state as such, Hawkins said, “I saw the cocaine, yes, so I did see the trace levels [of cocaine]. [But] [i]t was below my reportable cutoff.” At the conclusion of the hearing, the trial court found that Hawkins’s testimony “is reliable and relevant. The defense objection is overruled. It will be permitted before the jury.”
At trial and in the presence of the jury, Hawkins testified that she detected trace levels of cocaine and cocaine metabolite in Bekendam’s blood sample. Specifically to the cocaine detected by use of the GCMS test, Hawkins testified that she saw trace amounts of cocaine in Bekendam’s blood that were “below my reportable limit that I’m allowed to report.” Hawkins said that the amount of metabolite she detected in Bekendam’s blood was “one of the larger amounts that I have reported of [b]enzoy-lecgonine[,] so it’s consistent with a large amount of cocaine use or a habitual use of cocaine.” When asked whether Bekendam had cocaine in her system at the time she ran the red light, Hawkins testified, “Since I saw cocaine in the sample at trace amounts [at the time the tests were conducted], based on the short half-life of cocaine and the fact that it degrades in the blood tube, [Bekendam’s cocaine blood level] ... may have been significantly higher at the time” Bekendam ran the red light. Hawkins said that it was her opinion that at the time Bekendam ran the red light, Bekendam would have had cocaine in her bloodstream.
The jury returned a verdict of guilty and set Bekendam’s punishment at twenty years’ confinement and a $10,000 fine. The trial court entered judgment accordingly. This appeal followed.
III. Discussion
In her sole issue, Bekendam argues that the trial court erred by allowing Haw*362kins to testify (1) that a trace amount of cocaine was present in Bekendam’s blood at the time of the blood draw and (2) that cocaine would have been in her bloodstream at the time she was operating her SUV when it collided with the other vehicle.
Bekendam’s argument is that Hawkins failed to follow the “standards and procedures” of the Texas Department of Public Safety (DPS) when she testified to the amounts of cocaine present in Bekendam’s blood at both of these times. Bekendam’s argument is predicated on the notion that because DPS requires a two-step procedure by its forensic scientists when screening blood samples for drugs, and that under this procedure the department as a policy does not include in its lab reports any positive test result whenever the second step to that procedure does not indicate a threshold level of certain drugs, Hawkins’s testimony was “inherently unreliable and therefore irrelevant” when she testified that she did in fact find trace amounts of cocaine in Bekendam’s blood sample using both tests. So, Bekendam argues, even though there were trace amounts of cocaine in her system at the testified-to times, Hawkins should not have been allowed to testify to the matter because she should have been bound by the department’s policies for reporting the presence of cocaine.
We review the trial court’s decision on the qualifications of an expert or the reliability of her testimony for an abuse of discretion. See Hernandez v. State, 53 S.W.3d 742, 750 (Tex.App.-Houston [1st Dist.] 2001, pet. ref'd). A trial court abuses its discretion when its decision lies outside the zone of reasonable disagreement. Casey v. State, 215 S.W.3d 870, 879 (Tex.Crim.App.2007). An expert may testify on scientific, technical, or other specialized subjects if the testimony would assist the factfinder in understanding the evidence or determining a fact issue. See Tex.R. Evid. 702. The trial court may exclude scientific testimony or evidence that is not reliable. See Hernandez, 127 S.W.3d at 218.
To be considered reliable, evidence derived from a scientific theory must satisfy three criteria: (a) the underlying scientific theory must be valid; (b) the technique applying the theory must be valid; and (c) the technique must have been properly applied on the occasion in question. Kelly, 824 S.W.2d at 573; see also Hartman v. State, 946 S.W.2d 60, 62-63 (Tex.Crim.App.1997) (applying Kelly standard to all scientific evidence, whether novel or not, that is offered under Tex.R. Evid. 702).
It is the third criterion, whether the scientific technique in question has been properly applied, that Bekendam attacks. Bekendam sets forth the proposition that the failure to follow DPS’s policy regarding testing blood samples for illicit drugs is the equivalent of failing to properly apply the scientific technique on the occasion in question.5 But the equating of the depart*363ment’s policy with any given scientific technique is erroneous. Indeed, within the department’s policy for drug screening, two specific scientific techniques are utilized. First, as Hawkins testified, the department utilizes EMIT to determine whether a class of drugs exists in a given sample. If the EMIT test is positive for a class of drugs, including cocaine, then the sample is tested under another scientific technique; namely, the GCMS test. Therefore, contrary to the manner in which Bekendam would have us approach our analysis, we must determine whether the trial court abused its discretion by allowing Hawkins to testify to the results that she ascertained by using the EMIT and GCMS tests. Hernandez v. State, 116 S.W.3d 26, 27-29 (Tex.Crim.App.2003).
In this case, the underlying scientific theory and techniques are not only accepted as valid by the relevant scientific community, they also have been accepted by a number of trial courts and reviewing courts as reliable. Id. As Presiding Judge Keller discussed in her concurring opinion in Hernandez, the “EMIT system has been overwhelmingly accepted as reliable. The reliability of [the EMIT] test [as a screen for broad categories of drugs] has been litigated extensively before fact-finders, with the parties being able to offer live testimony and to conduct cross-examination.” Hernandez, 116 S.W.3d at 42 (Keller, P.J., concurring) (citing Jones v. United States, 548 A.2d 35, 44-46 (D.C.1988)); see also Spence v. Farrier, 807 F.2d 753, 756 (8th Cir.1986) (citing cases and discussing general acceptance of EMIT test results as relevant evidence). Following Judge Keller’s concurrence in Hernandez, the court of criminal appeals recently held that “the reliability of even a single, unconfirmed EMIT test has been sufficiently established that it meets the first two Kelly prongs.” Somers v. State, 368 S.W.3d 528, 545 (Tex.Crim.App.2012). And much like the facts of this case, the Somers court found it significant that the confirming GCMS test “did in fact show traces of cocaine ... but at a level below the minimum required by DPS protocol to be reported as positive.” Id. at 544.
Similar to EMIT, GCMS has for some time been considered the “Golden Rule” in the field of toxicology to verify or confirm the results of an EMIT test. Bolieu v. State, 779 S.W.2d 489, 490 (Tex.App.-Austin 1989, no writ); see also Combs v. State, 6 S.W.3d 319, 322 (Tex.App.-Houston [14th Dist.] 1999, no pet.) (“Texas and Federal courts have found the gas chromatography test to be a reliable method for identifying compounds, and it has been generally accepted] in the scientific community.”).
Here, the trial court conducted a hearing where the expert testified to her qualifications; to the utilization of both the screening and the confirmation tests she utilized; that these tests are generally accepted in the scientific community; and that testimony concerning these tests has been admitted in courts “across the State of Texas and the United States.” Given the general acceptance of these tests within both the scientific and judicial communities, we cannot say that the trial court’s decision to allow the expert witness to testify to her findings was outside the zone of reasonable disagreement. Casey, 215 S.W.3d at 879. It was certainly within the trial court’s discretion to determine that the State’s expert testimony regarding her analysis of Bekendam’s blood sample would assist the factfinder in understanding the evidence or in determining the question of whether Bekendam had cocaine in her system while she operated her *364SUV during the time of the incident. See Tex.R. Evid. 702.
We conclude and hold that the trial court’s determination to allow the State’s expert to testify to the level of cocaine found in Bekendam’s blood sample — both at the time of the blood draw and at the time of the incident — falls within the zone of reasonable disagreement, even though Hawkins identified trace levels of cocaine and cocaine metabolite that were below mínimums set by DPS’s policy. We overrule Bekendam’s sole issue.
IV. Conclusion
Having overruled Bekendam’s sole issue on appeal, we affirm the trial court’s judgment.
WALKER, J., filed a dissenting opinion in which DAUPHINOT and GARDNER, JJ., join.. See Tex. Penal Code Ann. § 49.09(b) (West Supp.2012).
. See Daubert v. Merrell Dow Pharmaceuticals, Inc., 509 U.S. 579, 113 S.Ct. 2786, 125 L.Ed.2d 469 (1993); Kelly v. State, 824 S.W.2d 568, 573 (Tex.Crim.App.1992).
. The use of the terms "benzoylecgonine,” "the class of cocaine and cocaine metabolites,” and "cocaine” are routinely described in caselaw, and by the expert testimony found in those cases, as interchangeable terms when discussing EMIT test results for the drug cocaine. See, e.g., Matter of Gordon v. Brown, 84 N.Y.2d 574, 577, 620 N.Y.S.2d 749, 644 N.E.2d 1305, 1306 (N.Y.1994). Indeed, in Somers, both the court of appeals and the court of criminal appeals refer to the results of EMIT as a positive test result for cocaine. Somers v. State, 333 S.W.3d 747, 753 (Tex.App.-Waco 2010) ("As previously discussed, the EMIT test was positive for cocaine, but the confirmation [GCMS] test was negative.”), overruled on other grounds by 368 S.W.3d 528, 530 (Tex.Crim.App.2012) ("The [EMIT] results were positive for both cocaine and amphetamines."). This language is used by both courts despite their discussions that what is actually being detected using EMIT is cocaine's metabolite, benzoylecgonine. Som-ers, 333 S.W.3d at 751 ("The [EMIT] test was positive for benzoylecgonine, called cocaine and its metabolites class.”); see also Somers, 368 S.W.3d at 532 ("EMIT actually tests for the existence of benzoylecgonine, not cocaine.”). But neither court is being "contrary” to the record in that case. Unlike some classes of drugs that EMIT screens for, cocaine is in a class of its own. Somers, 368 S.W.3d at 531 ("the [EMIT] results indicated a possible positive for benzoylecgonine, or ‘cocaine and its metabolites’ ”). For illustration, EMIT also screens for a class of "amphetamines,” but a positive result in this class does not necessarily indicate the specific drug ingested. See Martin v. State, 214 Ga.App. 614, 617, 448 S.E.2d 471, 474 (1994), cert, denied, (1995) (explaining that after EMIT results indicated the presence of an "amphetamine-like substance,” additional testing using GCMS confirmed the presence of methamphetamine). But a positive result under EMIT in the cocaine and cocaine metabolite class reveals the drug ingested, co*361caine. See Somers, 368 S.W.3d at 532 ("[The expert] then, agreed that EMIT is a reliable presumptive test to determine whether cocaine has been ingested.”). This is so because as Hawkins testified in this case, “Ben-zoylecgonine only comes from cocaine.” In Somers, Hawkins was also an expert witness. Id. Throughout Somers, when characterizing Hawkins’s testimony regarding EMIT in general, the court of criminal appeals routinely refers to the results of EMIT as a positive test for cocaine. Id. When it comes to cocaine, the limitation in EMIT is not its inability to detect the drug ingested by the host; an "EMIT test alone [will] not indicate how or when an individual ingested cocaine, how much was taken, or whether the individual was a habitual user.” Id. at 532-33. But as we know from Somers, “the results of a [GCMS] test would not indicate these facts either.” Id.
. See Stedman’s Medical Dictionary 631 (28th ed. 2006).
. The converse of Bekendam’s position is correct pertaining to breath tests. That is, in a hearing regarding reliability of scientific evidence in a DWI prosecution at which the results of a breath test are challenged, all the trial court need do to satisfy its "gate-keeping’’ function is to determine whether the technique was properly applied in accordance with DPS rules on the particular occasion in question. Bolen v. State, 321 S.W.3d 819, 826-27 (Tex.App.-Amarillo 2010, pet. ref'd). This is so because the Legislature has already determined that the underlying science is valid and that the technique applying it is valid so long as it is administered by individuals certified by and using testing techniques approved by the DPS. Bolen, 321 S.W.3d at 826. But this rule does not remove the trial court’s gate-keeping function on expert testimony regarding techniques not administered in accor*363dance with DPS policy. Nor does this rule dictate that techniques not administered in accordance with DPS policy are per se unreliable.