DENVER - Calibration quality control problems affect 33 breathalyzer tests in Weld County, according to a report from the Colorado Department of Public Health and Environment.
The report indicates that the 33 individuals were tested on an Intoxilyzer 9000 machine in the Weld County Southwest Services Building that did not have the proper tolerance target entered during the initial certification process. It also finds that officers performing the tests did not identify unacceptable calibration results on those tests.
If the proper tolerances were entered into the machine properly, they would have stopped the test sequences automatically when the calibration check wavered out of the allowable range.
CDPHE's report indicates the machine's manufacturer, CMI Inc., told the department on May 9 that a DUI attorney from Sterling contacted them about a test conducted on March 8. That test indicated an out-of-range temperature on a peripheral instrument, called a Guth 12V500, that is also used to check the calibration of the Intoxilyzer 9000.
As a result, every result from the Guth 12V500s in use in Colorado was audited. That found two anomalous results from a single Intoxilyzer 9000 machine.
Further reviews of that machine identified the 33 tests that failed the quality control checks between August 30, 2013 and January 21, 2014. The work also confirmed that all of the other Intoxilyzer 9000s were properly calibrated, the report shows.
The report says the calibration of the instrument involved is not in question but it cannot endorse the test results in the 33 involved cases "to remain consistent with laboratory (quality control) best practices."
CDPHE's report also recommended that all affected law enforcement agencies be notified about the affected cases.
Of the 33 cases, 24 were from the Colorado State Patrol, four were from the Frederick Police Department, two were from both the Firestone Police Department and Weld County Sheriff's Office and one was from the Dacono Police Department.