At Grade 2 the largest block is Sample Collection, Testing and Analysis (32% of the exam).
For bench analysts in water and wastewater laboratories — running the tests, keeping the quality control defensible, and standing behind numbers that end up in a regulatory report.
Start studying Grade 2| Content area | % of the exam | |
|---|---|---|
| Sample Collection, Testing and Analysis | 32 | |
| Documentation, QA/QC, Regulatory Compliance and Ethics | 26 | |
| Equipment, Supplies and Facilities | 20 | |
| Safety | 10 | |
| Math | 12 |
Quality control: matrix spike recovery · an original practice item written only from publicly available sources, not a real exam question
A sample measures 4.0 mg/L. A portion spiked with 5.0 mg/L of analyte measures 8.6 mg/L. What is the spike recovery?
A. 92%
Recovery = (spiked result − unspiked result) ÷ spike added × 100 = (8.6 − 4.0) ÷ 5.0 × 100 = 92%. 172% forgets to subtract the native 4.0 mg/L; 115% divides the recovered amount by the native result instead of the spike added (4.6 ÷ 4.0); 215% divides the spiked result by the native result (8.6 ÷ 4.0).
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Topic coverage follows Laboratory Analyst Candidate Handbook, Version 05.01.23.02 (California Water Environment Association, effective May 2023). Practice questions are written only from publicly available sources (that outline and the regulations and references it cites); they are not real exam questions, which are confidential. Check current application requirements, fees and exam dates on the certifying body's own page: official certification page.
Questions, flashcards, and explanations are AI-written from publicly available sources only: the exam content outlines and candidate materials each certifying body publishes without restriction, and the regulations and technical references they cite. No confidential material is used, including actual exam questions, recollections of any exam sat by the author, or any handbook or document released under a confidentiality agreement. Content is then put through repeated review — regulatory values checked against primary sources, every calculation recomputed, and errors corrected — plus spot checks by the author, who holds California water operator certifications and a California civil engineering licence. Those spot checks are sampling, not a professional review: nothing here is stamped, sealed, or offered as engineering advice, and not every item has been individually verified, so mistakes can still slip through.