ADM Equipment Operation & Maintenance 2 — Questions and Answers
Question 1: When using a point-of-care urine immunoassay cup, a temperature strip reading of 90–100°F indicates which of the following?
- The specimen is invalid and must be rejected
- The specimen temperature is within acceptable range for a fresh void (Correct answer)
- The specimen has been adulterated with bleach
- The specimen must be sent to a confirmatory lab before reading
Correct answer: The specimen temperature is within acceptable range for a fresh void
A temperature between 90–100°F confirms the urine was freshly voided from the body, meeting validity requirements.
Question 2: What is the primary purpose of performing quality control (QC) runs on an onsite immunoassay drug testing analyzer?
- To fulfill DEA controlled substance registration requirements
- To ensure the instrument is performing within acceptable accuracy parameters (Correct answer)
- To calibrate the breathalyzer attachment
- To document chain of custody for forensic specimens
Correct answer: To ensure the instrument is performing within acceptable accuracy parameters
QC runs with known-positive and known-negative controls verify that the analyzer's results are accurate and reliable before testing patient specimens.
Question 3: A clinic's breathalyzer displays an 'Err 4' fault code during a patient test. What is the most appropriate next step?
- Record the result as 0.00 g/dL and proceed
- Refer to the manufacturer's troubleshooting guide and do not use the device until the error is resolved (Correct answer)
- Repeat the test immediately using the same mouthpiece
- Substitute a urine drug screen as equivalent evidence of alcohol use
Correct answer: Refer to the manufacturer's troubleshooting guide and do not use the device until the error is resolved
Error codes indicate a device malfunction; the manufacturer's guide must be consulted and the device must be taken out of service until the issue is corrected.
Question 4: Gas chromatography-mass spectrometry (GC-MS) is used as a confirmatory test for drug screening primarily because it:
- Produces results in under five minutes at the point of care
- Provides high specificity by identifying the exact molecular structure of a compound (Correct answer)
- Can be operated without laboratory technician training
- Detects alcohol at lower cutoff levels than immunoassay
Correct answer: Provides high specificity by identifying the exact molecular structure of a compound
GC-MS identifies compounds by their unique molecular fragmentation pattern, making it highly specific and resistant to cross-reactivity false positives.
Question 5: Which of the following best describes the correct procedure for reading a urine drug test strip after the manufacturer's specified reaction time has elapsed?
- Any line present, regardless of intensity, in the test region indicates a negative result (Correct answer)
- The absence of a line in the control region and presence in the test region indicates a positive result
- Two lines in both control and test regions indicate a positive result
- A test region line appearing after the time window may be read as a valid negative
Correct answer: Any line present, regardless of intensity, in the test region indicates a negative result
On a competitive immunoassay strip, any visible line in the test region—regardless of intensity—indicates a drug concentration below the cutoff and is read as negative.
Question 6: A urine specimen submitted for drug testing is found to have a creatinine level of 8 mg/dL and a specific gravity of 1.001. This specimen is most accurately classified as:
- Substituted (Correct answer)
- Adulterated
- Invalid
- Dilute
Correct answer: Substituted
Federal workplace drug testing guidelines classify a specimen as substituted when creatinine is less than 2 mg/dL and specific gravity is less than 1.0010 or greater than 1.0200; values of 8 mg/dL and 1.001 indicate dilution rather than substitution.
Question 7: How often should an evidential breath testing (EBT) device used in a DOT-regulated program be subject to an external calibration check?
- Every 24 hours
- Every 7 days or 150 tests, whichever comes first (Correct answer)
- Every 30 days
- Once per calendar year
Correct answer: Every 7 days or 150 tests, whichever comes first
DOT regulations (49 CFR Part 40) require EBT external calibration checks every 7 days or 150 tests, whichever occurs first, to ensure ongoing accuracy.
ADM Equipment Operation & Maintenance 2
When using a point-of-care urine immunoassay cup, a temperature strip reading of 90–100°F indicates which of the following?