CARO Study Guide 2026

Everything you need to pass the CARO exam in one place: the exam format, every topic to study, real practice questions with explanations, flashcards, and full-length practice tests. Free, no sign-up needed.

📋 CARO Exam Format at a Glance

110
Questions
180 min
Time Limit
70.00%
Passing Score

📚 CARO Topics to Study (69)

✍️ Sample CARO Questions & Answers

1. When draining oil from an ammonia vessel, which practice is safest?
✓ Use a self-closing (spring-loaded) drain valve with a second isolation valve, and never leave it unattended

A spring-loaded valve shuts if released, and constant attendance keeps an ammonia release from going unnoticed.

2. Before opening a section of ammonia piping for maintenance, which step is required first?
✓ Isolate, pump down, and lock out/tag out the section

Isolating, evacuating, and applying lockout/tagout protects workers from releases of energy and ammonia.

3. Why is it important to pitch refrigerant suction lines toward the compressor?
✓ To ensure oil and liquid refrigerant drain back to the compressor rather than trap in low spots

Suction lines are pitched toward the compressor so that oil and any liquid refrigerant flow back naturally, preventing oil logging in the evaporator and liquid slugging in the compressor.

4. Increasing the clearance volume in a reciprocating compressor cylinder will:
✓ Reduce volumetric efficiency

Gas trapped in the clearance space re-expands on the suction stroke, so less fresh suction gas enters each cylinder.

5. Where must ammonia pressure relief valves on a system ultimately discharge?
✓ To a safe location outdoors per code

Relief discharge must be piped to a safe outdoor location away from people, openings, and air intakes.

6. An operator measures a condenser pressure that is well above the saturation pressure for the liquid temperature leaving the condenser. What does this most likely indicate?
✓ Noncondensable gases are present

Pressure above the saturation pressure at the measured temperature points to air or other noncondensables in the condenser.

🎯 Free CARO Practice Tests

📖 CARO Guides & Articles

Your CARO Study Path
1. Learn with Flashcards → 2. Drill Practice Tests → 3. Take the Full Exam Simulation

What Practice Test Geeks adds beyond an AI chat for CARO

An AI chatbot can quiz you, but it can't reproduce the exam conditions or keep your record. Here you get:

  • A timed, full-length CARO mock exam — 110 questions in 180 minutes with a 70% pass mark, modeled on the official exam's question count and time limit, followed by a score report broken down by exam domain.
  • A fixed CARO question bank: the same test every attempt, so your score is comparable from one try to the next instead of changing with every regenerated quiz.
  • Progress saved on your device: completed tests, scores and missed questions stay in My Progress, so you can retake only what you got wrong.
  • A printable CARO cheat sheet you can print or save as a PDF.
  • CARO flashcards built from the same question bank.
  • Free CARO practice tests with the correct answer shown after each question.
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