Technician Certification Examination

Illinois Environmental Laboratory Technician Certification Examination Practice Questions And Correct Answers (Verified Answers) Plus Rationales 2026 Q&A | Instant Download Pdf

• What is the primary purpose of a Quality Assurance/Quality Control

(QA/QC) program in an environmental laboratory?

• To reduce laboratory staff
• To ensure the accuracy and reliability of test results
• To speed up sample analysis
• To decrease the number of tests performed

Rationale: A QA/QC program ensures that all laboratory data is accurate,

reliable, and reproducible.

• Which of the following is considered a physical water parameter?
• pH 1 / 4

• Turbidity
• Nitrate concentration
• Total coliforms

Rationale: Turbidity measures the cloudiness or haziness of water, which is

a physical property.

• What is the correct procedure if a sample container is found broken

upon receipt in the lab?

• Analyze as normal
• Ignore the sample
• Document the incident and request a new sample
• Use only part of the sample

Rationale: Broken samples compromise integrity; proper documentation

and resampling maintain QA/QC.

4. The chemical formula for common table salt is:

A. H2O

B. CO2

• NaCl
• KCl

Rationale: NaCl represents sodium chloride, common table salt.

• When calibrating a pH meter, what is the minimum number of

standard buffers required?

• One 2 / 4

• Two
• Three
• Four

Rationale: At least two standard buffers are required to calibrate for slope

and offset.

• What is the primary purpose of using blanks in laboratory analysis?
• To clean equipment
• To detect contamination in reagents or equipment
• To dilute samples
• To verify standards

Rationale: Blanks are analyzed to ensure no contamination affects sample

results.

• Which agency regulates the standards for drinking water in Illinois?

A. EPA

B. OSHA

• Illinois Environmental Protection Agency (IEPA)

D. FDA

Rationale: The IEPA sets and enforces environmental regulations, including

drinking water standards.

• What is the acceptable holding time for total coliform analysis in

drinking water?

• 6 hours 3 / 4

• 12 hours
• 24 hours
• 48 hours

Rationale: Samples must be analyzed within 24 hours of collection to

ensure accuracy.

• What is the principle behind colorimetric analysis?
• Measuring temperature
• Measuring light absorption by a colored solution
• Filtering solids
• Counting bacteria

Rationale: Colorimetric analysis quantifies analytes by their light

absorption properties.

• Which of the following is a microbiological water parameter?
• Turbidity
• E. coli
• pH
• Total dissolved solids

Rationale: E. coli is a bacteria used to indicate microbial contamination.

• What is the main reason for performing a method blank?
• To standardize equipment
• To ensure no contamination occurs from reagents or equipment
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