FREE CPO Certified Pool Operator Exam Guide 2026: PHTA Course, Water Chemistry Math, 74% Pass (Practice Questions)

Free 2026 CPO Certified Pool Operator exam guide: PHTA course (formerly NSPF), 50-question test, 74% pass score (37 of 50), MAHC 5th Edition (2024), LSI water balance math, 2-week study plan, and 5-year renewal rules.