Many programs have a “zero tolerance” policy for alcohol use. Their program policies frequently prohibit the use of any alcohol. Does this mean that any reading on an Alco-Sensor higher than .000 is a positive test and grounds for taking action against a client or employee? While it might seem logical that .000 is the only acceptable negative test result for a zero tolerance policy, AlcoPro recommends that agencies use a threshold of either .010 or .020 as a positive test. We do not recommend taking action on an alcohol test result lower than the threshold levels of .010 or .020.
The industry standard for laboratory drug testing is to set a numerical cut-off level for the drug being detected. If the drug is present at a concentration at, or above, the cut-off level the test is positive. If the drug is not present at or above the cut-off level, the test is negative. Cut-off levels vary from one drug to another. Scientists choose a cut-off level that 1), reliably indicates the presence of the drug and 2), and is at a level that the measuring instruments can reliably detect.
For example, the screening cut-off level for marijuana is 50 ng/ml. A negative drug test for marijuana means that drug was not present at a concentration of 50 ng/ml or greater. A negative drug test does not mean that there was zero amount of drug. A specimen can still contain drug below the cut-off level and be correctly identified as a negative test. A laboratory report simply says “negative” or “positive.” We never know if a small amount of drug was present in a specimen or if there was zero amount of drug.
The scientific principles of establishing cut-off levels that apply to drug testing also apply to alcohol testing. However, unlike a laboratory test in which we see only the report of “positive” or “negative,” when testing with an Alco-Sensor the operator sees the numerical result and we must make the determination of “negative” or “positive.”
We recommend using a .020 cut-off level for employee testing and other evidential alcohol testing applications. A .020 cut-off level is very conservative; there is no question that a person with .020 BAC has consumed alcohol, and there is no question that an Alco-Sensor can reliably detect this amount of alcohol. The U.S. Department of Transportation (DOT) uses this cut-off level in their mandatory alcohol testing programs. A policy that is based on the U.S. Department of Transportation alcohol testing regulation is easily defended.
When using a .020 threshold level, any test result of .019 or lower is considered a negative test.
We recommend using a .010 cut-off level for testing in non-evidential settings, such as alcohol treatment programs. AlcoPro, Inc. believes that .010 is a high enough alcohol concentration to reliably indicate that a person has consumed alcohol. And .010 is within the accuracy limits of the Alco-Sensors. (All three-digit Alco-Sensors have an accuracy of +/- .005. Two-digit Alco-Sensors have an accuracy of +/- .01.)
When using a .010 threshold level, any test result of .009 or lower is considered a negative test. We recommend that agencies do not take action on test results lower than .010.