A study was conducted at a nightclub to evaluate the performance of the Contralco Alcohol Breath Tester by having volunteers perform the test and interpret results in a real-world setting, compared against a quantitative breath alcohol device.
Nightclub study; User performance; Real-world setting
Clinical Evidence
Study Design
Population
Comparator
Key Endpoints
Nightclub User Study; Observational study in a real-world setting
Nightclub patrons/volunteers; Sample Size: 59 measures; Number of Sites: 1
LION quantitative breath alcohol device
Correct performance and interpretation of the test by consumers
Indications for Use
The Contralco Alcohol Breath Tester is an in vitro medical device to semi-quantitatively detect the presence of alcohol in the human breath. It is a disposable screening device for one-time use. The detector is available at several detection cutoffs: 0.02, 0.04, 0.05, 0.06, 0.08, and 0.10 relative percent Blood Alcohol Concentration (BAC). The device is used only as a screening device and is only an indication of the possible presence of alcohol in the blood of the test subject.
Device Story
Disposable, single-use breath alcohol screening device. Input: human breath sample collected via plastic bag. Principle of operation: chemical oxidation; breath vapors react with reagent crystals (Chromium VI oxide and sulfuric acid) inside a glass tube. Presence of alcohol oxidizes vapors to acetic acid, reducing indicator chemicals to chromium sulfate, causing a color change from yellow to light green. Output: visual color change indicating alcohol presence relative to a pre-calibrated cut-off (0.02, 0.04, 0.05, 0.06, 0.08, or 0.10% BAC). Used by consumers in non-clinical settings (e.g., nightclubs). User interprets results by observing the extent of color change. Provides a screening indication of potential blood alcohol presence; does not provide a definitive quantitative measurement.
Clinical Evidence
Prospective study conducted at a nightclub with 59 participants. Volunteers provided breath samples for the Contralco device and a quantitative LION comparator device. Results showed 98% effectiveness (58/59 measurements coherent). Study confirmed consumers could correctly perform and interpret the test according to package instructions.
Technological Characteristics
Reagent tube containing Chromium VI oxide and sulfuric acid on crystals; plastic bag for breath collection. Semi-quantitative colorimetric sensing principle. Dimensions/form factor: disposable tube and bag. No energy source required. Storage: 10°C to 40°C. No software or connectivity.
Indications for Use
Indicated for over-the-counter use by individuals to semi-quantitatively screen for the presence of alcohol in human breath at specific BAC cut-offs (0.02% to 0.10%).
Regulatory Classification
Identification
A breath-alcohol test system is a device intened to measure alcohol in the human breath. Measurements obtained by this device are used in the diagnosis of alcohol intoxication.
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# 510(k) SUBSTANTIAL EQUIVALENCE DETERMINATION DECISION SUMMARY ASSAY ONLY TEMPLATE
A. 510(k) Number:
k100879
B. Purpose for Submission:
New Device
C. Measurand:
Breath Alcohol
D. Type of Test:
Semi-quantitative visually read color change
E. Applicant:
Contralco
F. Proprietary and Established Names:
Contralco Single Use Breath-Alcohol Tester (0.02, 0.04, 0.05, 0.06, 0.08, and 0.10% BAC)
G. Regulatory Information:
| Product Code | Classification | Regulation Section | Panel |
| --- | --- | --- | --- |
| DJZ | Class I, reserved | 862.3050 | 91, Toxicology |
H. Intended Use:
1. Intended use(s):
See indication for use below.
1. Indication(s) for use:
The Contralco Alcohol Breath Tester is an in vitro medical device to semi-quantitatively detect the presence of alcohol in the human breath. It is a disposable
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screening device for one-time use. The detector is available at several detection cutoffs: 0.02, 0.04, 0.05, 0.06, 0.08, and 0.10 relative percent Blood Alcohol Concentration (BAC). The device is used only as a screening device and is only an indication of the possible presence of alcohol in the blood of the test subject.
3. Special conditions for use statement(s):
For Over the Counter use
4. Special instrument requirements:
Not applicable.
# I. Device Description:
The Contralco Alcohol Breath Tester device is made up of 2 parts: the reagent tube and the plastic bag. Yellow crystals in the reagent tube are coated with Chromium VI oxide and sulfuric acid. The amount of these indicator chemicals is adjusted according to the selected cut-off of the tester. The user exhales into the reagent tube and fills the plastic bag with exhaled air. A color change is produced when alcohol vapors (squeezed from collected exhaled air in the plastic bag portion of the tester) are oxidized to acetic acid and the indicator chemicals change to chromium sulfate. The majority of crystals change from yellow to light green when alcohol vapors are present at a level equal to or exceeding the labeled cut-off of the tester.
# J. Substantial Equivalence Information:
1. Predicate device name(s):
Redline disposable Alcohol Breath Tester
2. Predicate 510(k) number(s):
k072953
2. Comparison with predicate:
| | Candidate Device | Predicate (k072953) |
| --- | --- | --- |
| Indication for use | Detect the presence of alcohol in the human breath | Same |
| Target Populations | Over the Counter | Same |
| Anatomical Site | Mouth | Same |
| Test sample | Human Breath | Same |
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| Composition of Reagent | Yellow Crystals | Same |
| --- | --- | --- |
| Collection Device | Plastic bag | Same |
| Blowing Time | 12 seconds | Same |
| Result Interpretation | Extent of color change | Same |
| Measurement Range | Separate devices are pre-calibrated to turn color at different cut-offs: 0.02%, 0.04%, 0.05%, 0.06%, 0.08%, 0.10% | Separate devices are pre-calibrated to turn color at different cut-offs: 0.02%, 0.04%, 0.05%, 0.08%, 0.10% |
| Protection of alcohol breath test against humidity | The reactant is placed in a glass tube with opercula at both extremities | Amorphous silica gel particles act as protective barrier at either end of tube |
K. Standard/Guidance Document Referenced (if applicable):
None referenced.
L. Test Principle:
The Contralco alcohol breath tester contains chemicals that change color in the presence of alcohol in human breath. First, the user pushes in both ends of the glass tube, sliding them until the dotted lines. Secondly, the user blows into the blue valve, filling the plastic bag with one breath only and completely inserts the blue perforation of the glass tube into the blue valve. Thirdly, the user pushes the plastic bag slowly, in about 12 seconds, until it is completely emptied. On contact with alcohol, the reactant will turn green. Each device has a black line which indicates the cut-off concentration for each device. If the green color reaches or exceeds the black line, the user has exceeded the allowed limit of alcohol per liter of air.
M. Performance Characteristics (if/when applicable):
1. Analytical performance:
a. Precision/Reproducibility:
The sponsor evaluated the precision and accuracy for each of the six Contralco Alcohol Breath Testers (0.02, 0.04, 0.05, 0.06, 0.08, and 0.1% BAC) using a Breath Alcohol Sample Simulator, which provides an alcohol-in-air test sample with known alcohol concentrations, flow rate, and air composition. On contact with alcohol, the reactant will turn green. Each device has a black line which indicates the cut-off concentration for each device. If the green color reaches or exceeds the black line, the user has exceeded the cut-off concentration and the result is considered positive. If the
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green color fails to reach the black line, the result is considered negative.
Testing was performed by 10 individuals under 5 different lighting sources using 20 Contralco Breath Alcohol Testers at each cutoff concentration. The concentrations used were 0% BAC, 60% below the cut-off concentration, and 60% above the cut-off concentration.
The table below shows the number of devices that resulted in the expected outcome (negative or positive) of the number of devices evaluated.
| | Concentration | 0.02 | 0.04 | 0.05 | 0.06 | 0.08 | 0.1 |
| --- | --- | --- | --- | --- | --- | --- | --- |
| Fluorescent | 0% | 200/200 | 200/200 | 200/200 | 200/200 | 200/200 | 200/200 |
| | -60% of cut-off | 200/200 | 200/200 | 200/200 | 200/200 | 200/200 | 200/200 |
| | +60% of cut-off | 200/200 | 200/200 | 200/200 | 200/200 | 200/200 | 200/200 |
| Daylight | 0% | 200/200 | 200/200 | 200/200 | 200/200 | 200/200 | 200/200 |
| | -60% of cut-off | 200/200 | 200/200 | 200/200 | 200/200 | 200/200 | 200/200 |
| | +60% of cut-off | 200/200 | 200/200 | 200/200 | 200/200 | 200/200 | 200/200 |
| Incandescent | 0% | 200/200 | 200/200 | 200/200 | 200/200 | 200/200 | 200/200 |
| | -60% of cut-off | 200/200 | 200/200 | 200/200 | 200/200 | 200/200 | 200/200 |
| | +60% of cut-off | 200/200 | 200/200 | 200/200 | 200/200 | 200/200 | 200/200 |
| Sodium Vapor | 0% | 200/200 | 200/200 | 200/200 | 200/200 | 200/200 | 200/200 |
| | -60% of cut-off | 200/200 | 200/200 | 198/200 | 200/200 | 200/200 | 200/200 |
| | +60% of cut-off | 200/200 | 200/200 | 200/200 | 200/200 | 200/200 | 200/200 |
| Mercury Vapor | 0% | 200/200 | 200/200 | 200/200 | 200/200 | 200/200 | 200/200 |
| | -60% of cut-off | 200/200 | 200/200 | 200/200 | 198/200 | 197/200 | 200/200 |
| | +60% of cut-off | 200/200 | 200/200 | 200/200 | 200/200 | 200/200 | 200/200 |
| % Agreement | | 100% | 100% | 100% | 99.86% | 99.90% | 100% |
b. Linearity/assay reportable range:
Not applicable. The assay is a semi-quantitative assay.
c. Traceability, Stability, Expected values (controls, calibrators, or methods):
The concentrations are prepared from commercially available solutions and are verified on certified evidential breath alcohol testers. These solutions are used to verify the cut-off concentration of the devices during manufacture.
The sponsor performed a stability assessment of all devices (0.02, 0.04, 0.05, 0.06, 0.08, and 0.1 % BAC) to evaluate the stability of the breath alcohol test results over time. This study served to validate the reported read time window claim of 2 to 15 minutes provided on the device labeling. Using simulated breath, (50) samples that were 60% below the device cut-off and (50) samples that were 60% above the cut-off were randomized and blinded prior to interpretation by (5) individuals at the end of 2, 5, 8, 11, and 15 minutes. Identical results were obtained for all devices at each time point tested. The results are presented in the table below:
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| | Contralco Alcohol Breath Tester Results (Cut-off: 0.02, 0.04, 0.05, 0.06, 0.08, 0.1) | |
| --- | --- | --- |
| Time | -60% of cut-off | +60% of cut-off |
| | | |
| 2 min | 50/50 Negative | 50/50 Positive |
| 5 min | 50/50 Negative | 50/50 Positive |
| 8 min | 50/50 Negative | 50/50 Positive |
| 11 min | 50/50 Negative | 50/50 Positive |
| 15 min | 50/50 Negative | 50/50 Positive |
d. Detection limit:
The NHTSA guidelines do not specifically address the detection limit of breath alcohol devices but require testing at a % BAC of zero (blank reading) to assess the possibility of false positives. The sponsor included a zero concentration sample in their precision study above. Non-alcoholic breath was used as the sample. There were no false positives observed when measuring zero concentration samples.
e. Analytical specificity:
The sponsor performed the following studies for each cut-off concentration (0.02, 0.04, 0.05, 0.06, 0.08, 0.10 %BAC) to evaluate the potential interference on the test results from cigarette smoke, temperature, and vibration.
Cigarette Smoke – (5) alcohol-free volunteers were asked to conduct (4) breath alcohol tests for each device cut-off concentration while smoking a cigarette. The testing was spread out to cover the duration of time it took to completely smoke a cigarette. The Contralco Alcohol Breath Testers produced no false positive or false negative results under these conditions.
Temperature – The sponsor assessed the effect of temperature at 10 and 40°C. A total of (40) different devices were stored and tested at each temperature for each cut-off concentration. Using simulated breath, (20) samples that were 60% below the device cut-off and (20) samples that were 60% above the cut-off were tested. The results are presented in the table below:
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| | Contralco Alcohol Breath Tester Results | | | | |
| --- | --- | --- | --- | --- | --- |
| | 10°C | | | 40°C | |
| Cut-off | -60% of cut-off | +60% of cut-off | | -60% of cut-off | +60% of cut-off |
| | | | | | |
| 0.02 | 20/20 Negative | 20/20 Positive | | 20/20 Negative | 20/20 Positive |
| 0.04 | 20/20 Negative | 20/20 Positive | | 20/20 Negative | 20/20 Positive |
| 0.05 | 20/20 Negative | 20/20 Positive | | 20/20 Negative | 20/20 Positive |
| 0.06 | 20/20 Negative | 20/20 Positive | | 20/20 Negative | 20/20 Positive |
| 0.08 | 20/20 Negative | 20/20 Positive | | 20/20 Negative | 20/20 Positive |
| 0.1 | 20/20 Negative | 20/20 Positive | | 20/20 Negative | 20/20 Positive |
Vibration- A total of (40) different devices for each cut-off concentration were placed in a box and mounted on a magnetic agitator for 5 minutes. Using simulated breath, (20) samples that were 60% below the device cut-off and (20) samples that were 60% above the cut-off were tested. The results are presented in the table below:
| | Contralco Alcohol Breath Tester Results | |
| --- | --- | --- |
| | -60% of cut-off | +60% of cut-off |
| Cut-off | | |
| 0.02 | 20/20 Negative | 20/20 Positive |
| 0.04 | 20/20 Negative | 20/20 Positive |
| 0.05 | 20/20 Negative | 20/20 Positive |
| 0.06 | 20/20 Negative | 20/20 Positive |
| 0.08 | 20/20 Negative | 20/20 Positive |
| 0.1 | 20/20 Negative | 20/20 Positive |
As an added precaution, the device is wrapped inside a bag to protect the tester from light. The manufacturer's labeling instructs the user to wait 20 minutes after drinking before taking a reading, to avoid smoking during the test, and to store the device in a dark place between 10°C and 40°C.
f. Assay cut-off:
Each device will produce a blue-green color at or above the following cut-off concentration: 0.02, 0.04, 0.05, 0.06, 0.08, 0.10 % BAC.
2. Comparison studies:
a. Method comparison with predicate device:
The sponsor performed a consumer study to determine if consumers could correctly use and interpret the device using only the supplied User's Manual, and to compare the results to a professional quantitative device (the LION device). The study was conducted at the exit of a nightclub. Each participant took their breath alcohol reading with the 0.05% Contralco tester and recorded their result. Immediately afterward, the participants were administered a breath alcohol test using the LION operated by a trained individual. A total of
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59 measures were taken. The reported age range of the participants was from 21 to 50 years of age. There were 38 males and 21 females who participated in the trial. Accuracy results are presented in the table below:
| Contralco 0.05% Tester Result | Quantitative Results | | | |
| --- | --- | --- | --- | --- |
| | Less than 60% the cut off (<0.02%) | Near Cut-off Negative (0.02 to 0.05%) | Near Cut-off Positive (>0.05 to 0.08%) | More than + 60% of cut-off (> 0.08%) |
| Positive | 0 | 0 | 10 | 17 |
| Negative | 18 | 13 | 1 | 0 |
After the study, participants were asked questions about ease of use and interpretation. The results are presented below:
| Question | Strongly Disagree | Disagree | Don’t Know | Agree | Strongly Agree |
| --- | --- | --- | --- | --- | --- |
| The Contralco instructions are easy to understand and follow | 0 | 0 | 0 | 16 | 43 |
| It is easy to see and read the Contralco results | 0 | 0 | 0 | 25 | 34 |
b. Matrix comparison:
Not applicable. This device may be used with breath samples only.
3. Clinical studies:
a. Clinical Sensitivity:
Not applicable.
b. Clinical specificity:
Not applicable.
c. Other clinical supportive data (when a. and b. are not applicable):
4. Clinical cut-off:
Not applicable.
5. Expected values/Reference range:
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For this type of device, alcohol should not be detectable in the breath of persons who have not ingested alcohol.
**N. Proposed Labeling:**
The labeling is sufficient and it satisfies the requirements of 21 CFR Part 809.10.
**O. Conclusion:**
The submitted information in this premarket notification is complete and supports a substantial equivalence decision.
8
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