RSO Study Guide 2026
Everything you need to pass the RSO 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.
📋 RSO Exam Format at a Glance
📚 RSO Topics to Study (22)
✍️ Sample RSO Questions & Answers
1. An RSO is working with a source of I-131, which has a half-life of approximately 8 days. If the initial activity is 40 mCi, what will the activity be after 24 days?
24 days equals 3 half-lives (24/8 = 3), so the activity decreases by half three times: 40 → 20 → 10 → 5 mCi.
2. A hospital's pathology waste is found to contain a patient's tissue with measurable I-131 activity. This waste should be:
Tissue containing I-131 is radioactive waste; given I-131's 8-day half-life, decay-in-storage is practical, and disposal must comply with the license and applicable state/NRC regulations.
3. Indirect action in radiation biology refers to:
Indirect action involves radiation ionizing water molecules in cells to produce hydroxyl radicals and other reactive species that then diffuse to and damage DNA.
4. A whole-body counter is used to measure:
A whole-body counter uses large-volume gamma detectors positioned around the body to detect and quantify internally deposited gamma-emitting radionuclides in organs and tissues.
5. Which nuclear process results in the emission of a positron (β+)?
Beta-plus decay occurs when a proton converts to a neutron inside the nucleus, emitting a positron and a neutrino.
6. Liquid scintillation waste containing H-3 or C-14 may be disposed of by sanitary sewer only if:
NRC 10 CFR 20.2003 and license conditions specify allowable concentrations and total annual discharge quantities for sewer disposal; both the concentration and total limits must be met.
🎯 Free RSO Practice Tests
📖 RSO Guides & Articles
What Practice Test Geeks adds beyond an AI chat for RSO
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 RSO mock exam — 100 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 RSO 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 RSO cheat sheet you can print or save as a PDF.
- RSO flashcards built from the same question bank.
- Free RSO practice tests with the correct answer shown after each question.