04314564 is referenced by 27 patents and cites 5 patents.

A method and apparatus for determining the alcohol concentration in the blood of a person by testing the person's breath, including, maintaining at least a minimum flow rate for the person's breath to form a test sample of the breath, measuring the alcohol amount in the test sample, measuring the increase in humidity in the test sample over ambient humidity and finding the ratio between the alcohol amount and the increase in humidity. This ratio is proportional to the actual alcohol concentration in the person's blood and cannot be disquised by a person wishing to falsify the results of the test.

Title
Method and apparatus for determining alcohol concentration in the blood
Application Number
6/112231
Publication Number
4314564
Application Date
January 15, 1980
Publication Date
February 9, 1982
Inventor
Scato Albarda
Gross Schenkenberg
DE
Agent
McGlew and Tuttle
Assignee
Dragerwerk Aktiengesellschaft
DE
IPC
A61B 5/00
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