Crime threshold in blood
- Input
- 0,6 g/L
- Expected output
- 0,06 g/dL
The calculator works internally in g/dL (the toxicology standard) and converts to g/L and mg/L of breath to compare against the law.
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brazil drunk driving legal limit
The short answer is: there is no "allowed" alcohol limit for driving in Brazil, the tolerance for the administrative infraction is zero from any detected concentration. What does exist is a higher threshold (0.6 g/L of blood or 0.3 mg/L of breath) at which the situation also becomes a traffic crime. This page opens the calculator with a 65 kg female profile already filled in; add the single dose from the example below to illustrate the point.
The calculator works internally in g/dL (the toxicology standard) and converts to g/L and mg/L of breath to compare against the law.
The 2-to-1 equivalence the law uses between blood concentration and exhaled breath.
Classic Widmark uses a fixed distribution factor (r), 0.68 for men and 0.55 for women, a population average. The Watson/Forrest method computes an individualized factor from your estimated total body water, based on height and weight, divided by weight, which tends to be closer to reality for people whose body composition falls outside Widmark's average, for example in cases of obesity.
This falls outside what this calculator does (it only estimates BAC), but it is worth knowing that refusing the test carries its own administrative consequences under the CTB, and other means of establishing impairment (a clinical exam, video, witnesses) can also be used. Check the law or a legal professional for that specific point.
Do not count on that. The error margin is a technical correction for the instrument (about 0.04 mg/L), not a tolerance for allowed alcohol, and your real blood alcohol concentration does not change because of it, only the reading officially considered for the citation does.
This is an educational estimate, not a measurement of your real blood alcohol. Individual variation is large, and the tool does not know whether you ate, took medication, or have a different tolerance than average. In Brazil, the tolerance for the administrative infraction is zero from any detected alcohol concentration (CTB article 165). The only reliably correct decision after drinking is not to drive.
Watson/Forrest computes the distribution factor from your height and weight instead of using a fixed average per sex.
No drinks added yet. Add at least one to calculate BAC.
This number is not permission to drive. After drinking, do not drive, even with a low or zero result.
Add at least one drink to see the curve.
All the math runs in your browser. No profile or drink data is ever sent to a server.