SMRs & radiation-safety fundamentals: study guide & quizzes

Sub-topics

• Fission & reactor basics

  Every power reactor, large or small, runs on the same physics: a controlled chain reaction of fissions that turns nuclear binding energy into heat.

  Practice questions in review

• Reactor types

  Reactors are classified mostly by their coolant and moderator. Those two choices drive the pressure, temperature, fuel and safety systems of the whole plant.

  Practice questions in review

• SMR concepts

  A small modular reactor is not a new kind of physics. It is a different way of building and operating reactors: smaller units, made in factories, with simpler safety systems.

  Practice questions in review

• Advanced designs & fuels

  Beyond small light-water reactors, many advanced designs change the fuel, the coolant or both. This page explains the main ideas at a general level, without ranking vendors.

  Practice questions in review

• Types of radiation

  Ionizing radiation has enough energy to strip electrons from atoms. The kind of radiation decides how far it travels, what stops it and whether it is mainly an external or internal hazard.

  Practice questions in review

• Radioactive decay

  Radioactive decay is random for any single atom but perfectly predictable for large numbers of them. That predictability is what the half-life captures.

  Practice questions in review

• Units & dose quantities

  US regulations still use rad, rem and curies alongside SI units. Knowing which quantity a number describes matters as much as converting it correctly.

  Practice questions in review

• Dose limits & health effects

  Dose limits only make sense against two reference points: what everyone receives from background and medicine, and the doses at which harm has actually been observed.

  Practice questions in review

• Shielding & ALARA

  Dose limits say how much is too much. ALARA says: whatever the limit, keep doses as low as is reasonably achievable. Time, distance and shielding are how.

  Practice questions in review

• US regulatory framework

  Who regulates a reactor, a gauge or a national laboratory depends on what it is and who owns it. This page maps the main laws and rules at a general level.

  Practice questions in review

Practice

A mixed 10-question topic quiz and spaced-repetition flashcards open here once their questions have been reviewed. Until then, each study page above has its explanation, FAQ and sources.

How the content is made

Every question has a written explanation and cites its source: US regulations (10 CFR), NRC regulatory guides, glossary and NUREG reports, DOE handbooks and Office of Nuclear Energy pages, and EIA and EPA explainers. These are US government works in the public domain. The explanations are our own. Questions are published only after review, and each one carries a version number so corrections are traceable. The study-page text is drafted from the same sources and cites them; check the source before relying on it.

The topics connect directly to the radiation calculators on this site: work a shielding or inverse-square question here, then check the numbers with the gamma dose-rate calculator.

Frequently asked questions

Who is this study guide for?

Newcomers to the nuclear industry, engineering students, technicians moving into SMR projects and anyone following SMR news who wants the fundamentals explained properly.

Are the questions checked before they are published?

Practice questions are drafted from public-domain US government sources and published only after review; no question is shown while it is still a draft. The explanations on the study pages are drafted from the same sources, which each page lists.

Does this prepare me for an NRC operator exam?

No. This is a general study aid. It is not training, a qualification or preparation for any regulated exam.

Do I need an account?

No. Everything runs in your browser, and your progress is stored locally. You can export and import it as a JSON file.