CCIL Sample Management and Preparation 2 — Questions and Answers
Question 1: When a laboratory receives a sample with insufficient volume for all requested analyses, what is the FIRST action that should be taken?
- Proceed with available volume and note which tests were omitted
- Contact the client to discuss options before testing begins (Correct answer)
- Split the sample equally among all tests regardless of priority
- Discard the sample and request a new one
Correct answer: Contact the client to discuss options before testing begins
Client communication is required before proceeding when sample volume is insufficient to ensure proper prioritization.
Question 2: Which chain-of-custody documentation element is MOST critical for legal defensibility of laboratory results?
- The date the analysis was completed
- A continuous record of every person who handled the sample (Correct answer)
- The laboratory accreditation number
- The analyst's educational credentials
Correct answer: A continuous record of every person who handled the sample
An unbroken chain of custody documenting every handler is essential to demonstrate sample integrity in legal proceedings.
Question 3: A soil sample for volatile organic compound (VOC) analysis must be stored at what temperature to prevent analyte loss?
- Room temperature (20–25°C)
- Refrigerated at 4°C (Correct answer)
- Frozen at -20°C
- Frozen at -80°C
Correct answer: Refrigerated at 4°C
VOC soil samples are preserved at 4°C to slow volatilization while preventing freezing that could alter the matrix.
Question 4: What is the purpose of a field blank in environmental sampling?
- To calibrate field instruments on-site
- To detect contamination introduced during sample collection and transport (Correct answer)
- To measure background analyte concentrations in the environment
- To verify the laboratory's detection limits
Correct answer: To detect contamination introduced during sample collection and transport
A field blank uses analyte-free water exposed to field conditions to identify contamination from collection, transport, or handling.
Question 5: Under CCIL accreditation standards, how long must a laboratory typically retain raw data and sample records?
- 1 year
- 3 years
- 5 years (Correct answer)
- 10 years
Correct answer: 5 years
CCIL and ISO/IEC 17025 generally require retention of records for a minimum of 5 years to support auditability.
Question 6: Which preparation method is appropriate for determining total metals in a water sample?
- Liquid-liquid extraction with methylene chloride
- Acid digestion with nitric acid (Correct answer)
- Solid-phase extraction on C18 cartridge
- Alkaline persulfate digestion
Correct answer: Acid digestion with nitric acid
Acid digestion with nitric acid dissolves metals from the water matrix, making them available for instrument analysis.
Question 7: A sample arrives at the laboratory with a broken seal. According to best practices, the laboratory should:
- Accept and analyze the sample since damage may be cosmetic
- Reject the sample immediately without documentation
- Document the condition, photograph it, and consult the client before proceeding (Correct answer)
- Reseal the container and note nothing in the logbook
Correct answer: Document the condition, photograph it, and consult the client before proceeding
Broken seals compromise sample integrity; proper documentation and client notification are required before any analytical decision.
CCIL Sample Management and Preparation 2
When a laboratory receives a sample with insufficient volume for all requested analyses, what is the FIRST action that should be taken?