<P> Breath analyzers assume that the subject being tested has a 2100 - to - 1 partition ratio in converting alcohol measured in the breath to estimates of alcohol in the blood . If the instrument estimates the BAC , then it measures weight of alcohol to volume of breath , so it will effectively measure grams of alcohol per 2100 ml of breath given . This measure is in direct proportion to the amount of grams of alcohol to every 1 ml of blood . Therefore , there is a 2100 - to - 1 ratio of alcohol in blood to alcohol in breath . However , this assumed partition ratio varies from 1300 : 1 to 3100 : 1 or wider among individuals and within a given individual over time . Assuming a true ( and US legal ) blood - alcohol concentration of . 07 % , for example , a person with a partition ratio of 1500 : 1 would have a breath test reading of . 10 % -- over the legal limit . </P>
<P> Breath analyzers assume that the subject being tested has a 2100 - to - 1 partition ratio in converting alcohol measured in the breath to estimates of alcohol in the blood . If the instrument estimates the BAC , then it measures weight of alcohol to volume of breath , so it will effectively measure grams of alcohol per 2100 ml of breath given . This measure is in direct proportion to the amount of grams of alcohol to every 1 ml of blood . Therefore , there is a 2100 - to - 1 ratio of alcohol in blood to alcohol in breath . However , this assumed partition ratio varies from 1300 : 1 to 3100 : 1 or wider among individuals and within a given individual over time . Assuming a true ( and US legal ) blood - alcohol concentration of . 07 % , for example , a person with a partition ratio of 1500 : 1 would have a breath test reading of . 10 % -- over the legal limit . </P>
what volume of breath does a breathalyzer collect
what volume of breath does a breathalyzer collect
grams of alcohol per 2100 ml
grams of alcohol per 2100 ml