Vet Students Breathed Alcohol Vapor and Blew a 0.087. What That Means for a Florida Breath Test

Ethanol is how an equine vet gets a clear ultrasound picture through a horse’s coat. It’s poured or sprayed on, sometimes more than a liter, and a vet called to a colic emergency at night may drive home right after the scan. Researchers at the University of Pisa and the University of Sydney wanted to know what an evidential breath test would say about that vet.

Most of the time, it said positive. It’s a small study with limits its authors spell out, and it says nothing about the machines Florida uses.

What the Study Did

The paper is Vitale and colleagues, “Breath Alcohol Test Results in Equine Veterinarians after Performing an Abdominal Ultrasound with Ethanol,” published in Veterinary Sciences in March 2023. Six fourth- and fifth-year veterinary students took part, five women and one man between 22 and 26. They reported having zero to two drinks a week, and they were asked not to drink in the 24 hours before each session.

Each student did six ultrasounds on the same 20-year-old mare, three pouring 90 percent ethanol from a jar and three spraying it, for 10, 30 or 60 minutes. That made 36 sessions, using 100 milliliters to 2.5 liters of ethanol, with a median of 500 milliliters. The room was 35 square meters and stayed closed during the scan. The students wore nitrile gloves “to avoid accidental dermal absorption,” which meant the alcohol reaching them came through the air.

Right after each scan, they blew into a Dräger Alcotest 7110, which the authors describe as an evidential infrared breath analyzer approved in Europe and Australia. Any positive was repeated every five minutes until the reading fell below 0.019 percent, the study’s cutoff for a negative.

What the Machine Read

On the first test, 30 of the 36 sessions came back positive. Eleven read above 0.050 percent, 19 read between 0.019 and 0.050, and six were negative. The authors add that “all participants tested positive at least 4/6 times.” The highest first reading in the paper’s table is 0.087, from a session that used more than a liter of ethanol, and a spray session reached 0.082.

The amount of ethanol made the biggest difference. The gaps between the volume groups were statistically significant, while pouring versus spraying and the length of the scan weren’t. When more than a liter was used, every session was positive on the first test, and the median reading 30 minutes later was still 0.023.

Time made a difference too. Half the sessions reached a negative result within about seven and a half minutes, and the longest took 60 minutes. The longest any session stayed above 0.050 was 35 minutes, and the median time above 0.050 was zero. The authors’ conclusion is practical: “It is recommended to wait at least 35 min before driving after performing an abdominal ultrasound.”

What the Study Doesn’t Show

It doesn’t test Florida’s machines. Florida’s rules approve the Intoxilyzer 8000 and 9000. The study’s Dräger pairs an infrared sensor with an electrochemical one and was set to report an estimated blood alcohol figure at a 2000-to-1 ratio, while Florida’s breath limit is written in grams per 210 liters of breath. Nothing in the paper says how an Intoxilyzer would read the same breath.

It has no waiting period. The first test came immediately after the scan. Florida requires a 20-minute wait, covered below, and in this study half the sessions were negative within about seven and a half minutes.

Nobody measured blood. The authors “did not measure BAC,” meaning blood alcohol concentration, so they can’t say whether any alcohol reached the students’ blood. They suspect some did, because 60 minutes “seems to be too long a time” to clear the airways, but they “can only hypothesize” it.

It’s small. Six young, healthy volunteers, mostly women, one horse, mornings only, food not tracked, and a closed room where, the authors concede, leftover alcohol in the air may have played a part. They write that “the results cannot be extrapolated to other situations.”

What the study does support is narrower. Breathing enough alcohol vapor in a closed space can put alcohol on an evidential breath test right afterward, and the effect grows with the amount of ethanol and fades with time.

Florida’s Breath Test Rules

Under section 316.193(1)(c), Florida Statutes, it’s DUI to drive or be in actual physical control of a vehicle with “a breath-alcohol level of 0.08 or more grams of alcohol per 210 liters of breath.” Subsection (1)(a) is a separate way to prove DUI, by showing the person’s “normal faculties are impaired,” and it doesn’t depend on a breath number.

The machines and the procedure come from rules the Florida Department of Law Enforcement (FDLE) writes, in chapter 11D-8 of the Florida Administrative Code. Rule 11D-8.003 names the approved instruments, “the CMI, Inc. Intoxilyzer 8000 and Intoxilyzer 9000.”

The waiting period is in rule 11D-8.007(3), last amended effective July 1, 2026. The operator or officer “shall reasonably ensure that the subject has not taken anything by mouth or has not regurgitated for at least twenty (20) minutes before administering the test.” The words are about the mouth. The rule doesn’t mention vapor breathed in before the stop, and it doesn’t use the phrase “mouth alcohol.”

The two-sample requirement sits in the definitions, rule 11D-8.002(12). An approved breath alcohol test is “a minimum of two samples of breath collected within fifteen minutes of each other, analyzed using an approved breath test instrument, producing two results within 0.020 g/210L.” If the first two results are more than 0.020 apart, “a third sample shall be analyzed.”

Where the Defense Is

The study helps only when the facts fit it. Someone who was in a closed room full of poured or sprayed alcohol right before a stop has a story it speaks to. Someone tested long after any exposure ended doesn’t, because nothing in the study lasted more than an hour.

Start with the timeline. Write down the product, roughly how much, for how long, in what kind of room, and when it ended. Then line it up against the stop, the arrest, and the time printed on the breath test. The study’s readings fell with each retest, so the minutes between exposure and test matter most.

Then the observation period. Bodycam and, where an agency records it, video from the breath testing room show who watched, from where, and for how long. If the 20 minutes can’t be accounted for, whether the test followed the rules becomes a real question.

Then the two samples. Results within 0.020 of each other meet the rule, but agreement alone says nothing about where the alcohol came from. Because the study’s readings dropped between retests, the size and direction of the gap between a person’s two samples, and the time between them, are worth showing an expert.

Then the machine’s records. Rule 11D-8.006 requires an agency inspection of each instrument “at least once each calendar month,” and rule 11D-8.0075 requires agencies to keep inspection and repair records for at least three years. FDLE posts Intoxilyzer 8000 instrument files, test data and inspection data online, and the rest can be requested as public records. The firm’s pages on breath test defense and the chapter 11D-8 rules go further into the machines and the rules, and every Florida criminal law that took effect October 1, 2026 covers this year’s other changes.

Common Questions

Can breathing alcohol fumes make you test positive on a breath test?

In one small 2023 study, it did, on 30 of 36 first tests and as high as 0.087, after veterinary students used 90 percent ethanol on a horse in a closed room. The effect faded with time, and the study didn’t test Florida’s machines or use a waiting period.

Does Florida’s 20-minute observation period cover alcohol fumes?

Rule 11D-8.007(3) requires 20 minutes in which the person “has not taken anything by mouth or has not regurgitated.” It says nothing about vapor breathed in earlier. In the study, 20 minutes was longer than half the sessions needed to clear, but not long enough for many that used more than a liter of ethanol.

Further Reading

1. Vitale V, et al., Breath Alcohol Test Results in Equine Veterinarians after Performing an Abdominal Ultrasound with Ethanol, Vet. Sci. 2023, 10(3), 222, full text on PubMed Central, doi:10.3390/vetsci10030222
2. Fla. Admin. Code R. 11D-8.007, observation period and operational procedures, Florida Administrative Code
3. Fla. Admin. Code R. 11D-8.002, definitions, including the approved breath alcohol test, Florida Administrative Code
4. Fla. Admin. Code R. 11D-8.003, approved breath test methods and instruments, Florida Administrative Code
5. Fla. Stat. 316.193, driving under the influence, Online Sunshine
6. Intoxilyzer 8000 Records, FDLE Alcohol Testing Program

This post is general information about Florida law, not legal advice, and it does not create an attorney-client relationship. The study discussed is Vitale V, Nocera I, van Galen G, Sgorbini M, Conte G, Aliboni B, Verwilghen D, “Breath Alcohol Test Results in Equine Veterinarians after Performing an Abdominal Ultrasound with Ethanol,” Veterinary Sciences 2023, 10(3), 222, doi:10.3390/vetsci10030222, read in full on PubMed Central. The law discussed is section 316.193, Florida Statutes, and Florida Administrative Code rules 11D-8.002, 11D-8.003, 11D-8.006, 11D-8.007 and 11D-8.0075, read on Online Sunshine and flrules.org, as of October 6, 2026.