On November 21st, 2013, NRC inspectors were performing an Access Authorization Fitness for Duty Baseline Inspection. A portion of the Baseline Inspection program works to verify the accuracy and completeness of performance indicators used to assess the performance of licensed facilities.
During the course of the investigation, the inspectors reviewed Laboratory testing results for blind samples.
Every licensee is required to submit blind performance test samples to laboratories to ensure their ability to determine specimen validity. These blind samples are adulterated, diluted, or substituted, and should be caught by the laboratories, who would then notify the licensee.
Indian Point blind samples are supplied by a vendor supplier, as are many other licensees.
The NRC inspector at Indian Point identified that a sample which had been submitted on March 3rd, 2013 failed to provide anticipated testing results. The sample should have been reported as diluted, but that laboratory report instead came back ‘Negative.’
Dilution is one of the most common methods for cheating a urine test. There are a few ways it is commonly done:
- Drinking lots of water before the test,
- Consuming diuretics to induce urination,
- Adding water or another liquid to the urine sample.
Most drug screening processes also analyze the sample’s urine specific gravity (USG), which measures the concentration of urine in the sample. Human urine generally registers between 1.010 and 1.025 USG.
The NRC inspectors also found that the specific gravity of the blind sample was reported back to the licensee outside of the expected range. The sample was known to have a concentration at or near 1.0015, below normal concentrations; however was reported at 1.0224 instead.
The blind sample errors were not identified by Indian Point personnel when the results were received back from the laboratory after being submitted on March 3rd. Subsequently, the licensee was found in violation of 10CFR26, and a corrective action for the event was that an extent of condition be performed to verify no other blind errors exist.
The Indian Point Medical Review Officer initiated an investigation of the laboratory. Additionally, an investigation of the vendor supplier who provided the blind sample will be initiated. The investigation will work to answer whether the laboratory failed to identify the blind test, or whether the supplier may have provided an invalid test, which would exonerate the laboratory testing procedures. It is also unclear why the issues with the test were not identified by Indian Point personnel upon receipt from the laboratory.
Source: NRC Event Notifications