PUBLIC LIBRARY / CALCULATOR

Breathalyzer: legally considered value (Brazilian Contran Resolution 432)

Applies the breathalyzer reference-value table of Contran Resolution 432/2013 and indicates whether the measurement constitutes an offence (article 165) or a crime (article 306).

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Check the population, units and version. The result shows the formula or classification; it does not make an automatic treatment decision.

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Method · Limits of application

CONTRAN 432/2013 Annex I: error 0.032/8%/30%; truncation to 2 decimals; Brazil scope

Resolution 432/2013 distinguishes the measured reading from the considered value after deducting the metrological error and requires an approved, verified instrument. Classification also permits other means, including blood and a set of psychomotor signs. A breathalyzer calculation alone is not a clinical assessment, proof of fitness to drive or a legal decision; the validity of the CTB and metrological legislation must be considered for the case.

Conditions of use

Check the population, units, inclusion and exclusion criteria, and version in the original source. A result alone does not establish a diagnosis, discharge decision or prescription.

Documented parameters

Breathalyzer measurement (MR) · mg/L of air

7/7 reference cases checked. Numerical tests are not clinical validation.

Sources and documentation

Documented formula

Transcribed from the source or a recorded revision; this is not a clinical recommendation.

VC = MR − EM, retaining two decimal places and discarding the rest (no rounding).

Maximum permissible error (EM): MR below 0.40 mg/L = 0.032 mg/L; MR from 0.40 to 2.00 mg/L = 8% of MR; MR above 2.00 mg/L = 30% of MR.

Offence (art. 165): MR ≥ 0.05 mg/L (VC ≥ 0.01). Crime (art. 306): MR ≥ 0.34 mg/L (VC ≥ 0.30 mg/L, equivalent to 6 dg/L in blood).

References

Identifier: etilometro-ctb

Original clinical content: Brazilian Portuguese.

Method version

CONTRAN 432/2013 Annex I: error 0.032/8%/30%; truncation to 2 decimals; Brazil scope

etilometro-ctb@native-2026-10-05+dec9fa1b484a

Brasil. Conselho Nacional de Trânsito. Resolução Contran nº 432, de 23 de janeiro de 2013 (procedimentos de fiscalização do consumo de álcool, Anexo I).

The bibliographic edition identifies the source. By itself, it proves neither full conformity of the formula nor clinical approval.

Synthetic cases checked (7)

Synthetic cases for checking the implementation, with no patient data.

Case 1

reference-001

Inputs

Breathalyzer measurement (MR): 0.05 mg/L of air

{
  "mr": 0.05
}

Expected result

{
  "vc": 0.01
}

Actual result

{
  "vc": 0.01,
  "em": 0.032
}

Case 2

reference-002

Inputs

Breathalyzer measurement (MR): 0.33 mg/L of air

{
  "mr": 0.33
}

Expected result

{
  "vc": 0.29
}

Actual result

{
  "vc": 0.29,
  "em": 0.032
}

Case 3

reference-003

Inputs

Breathalyzer measurement (MR): 0.34 mg/L of air

{
  "mr": 0.34
}

Expected result

{
  "vc": 0.3
}

Actual result

{
  "vc": 0.3,
  "em": 0.032
}

Case 4

reference-004

Inputs

Breathalyzer measurement (MR): 0.64 mg/L of air

{
  "mr": 0.64
}

Expected result

{
  "vc": 0.58
}

Actual result

{
  "vc": 0.58,
  "em": 0.0512
}

Case 5

reference-005

Inputs

Breathalyzer measurement (MR): 1 mg/L of air

{
  "mr": 1
}

Expected result

{
  "vc": 0.92
}

Actual result

{
  "vc": 0.92,
  "em": 0.08
}

Case 6

reference-006

Inputs

Breathalyzer measurement (MR): 2.5 mg/L of air

{
  "mr": 2.5
}

Expected result

{
  "vc": 1.75
}

Actual result

{
  "vc": 1.75,
  "em": 0.75
}

Case 7

reference-007

Inputs

Breathalyzer measurement (MR): 0.04 mg/L of air

{
  "mr": 0.04
}

Expected result

{
  "vc": 0
}

Actual result

{
  "vc": 0,
  "em": 0.032
}

Code and reproducibility

This tool’s code on GitHub

Download code and tests

Sources, version and reproduction instructions

README

Local installation

Code license: Apache-2.0

Guidelines and conditions

This repository’s license applies to the code. Third-party instruments, questionnaires, data and models remain subject to their owners’ conditions.

The code tests are technical checks. Clinical approval and professional translation review are recorded separately.

Relationship with cancer research

General context — relationship to be defined

A resource for general clinical contexts. This edition does not assign a specific oncological relationship; selecting it for a study requires a justified question, population and purpose.