RadCn.Tech

Health physics calculators

Decay data: ENSDF (NNDC) via IAEA NDS
Gamma dose rate (6CEN)
Objective 1.11.02
Exposure rate from a gamma point source using the handbook's 6CEN rule.
Inverse square law
Objective 1.11.07
Point-source intensity at a new distance, or the distance for a target intensity.
Line source
Objective 1.11.08
Estimate intensity or distance using the handbook’s line-source approximation.
Stay time
Objective 1.11.05
How long a worker may remain in a field given an allowable dose and dose already received.
Shielding (HVL / TVL)
Objective 1.11.13
Attenuation through half- and tenth-value layers, or the thickness for a target rate.
Radioactive decay
Objective 1.06.14
Activity after decay, back-decay to an earlier activity, or the time to reach a target.
Effective half-life
Objective 1.12.10
Radiological decay and biological elimination combined — always shorter than either.
Unit conversion
Objective 1.02.03
Convert between compatible units using the handbook’s conversion tables.

Check your work as you study

Use these calculators to check answers to practice problems. Results and accuracy notes are free. Paid membership adds worked solutions with substitutions, conversion steps and calculator keystrokesKey sequences for 14 calculator optionsScientific — commonly exam-legalTI-30XaTI-30X IIS / IIBTI-30XS MultiViewTI-34 MultiViewTI-36X ProCasio fx-991EX ClassWizCasio fx-115ES PlusCasio fx-300ES PlusSharp EL-W516TOn screen, no handheld neededRadCon calculator (on screen)Graphing / programmable — practice at homeTI-84 Plus CE (and TI-83/84 family)Casio fx-9750GIII / fx-9860GIIIHP 35sNot sure which you haveGeneric scientificChoose the calculator you use to practice. Check with your testing site which models are allowed in the exam. so you can follow the method.

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Look up half-lives and decay modes in the Chart of the Nuclides, using NUBASE2020 data.

Use these calculators for study and reference. For operational radiological work, follow your site’s controlled procedures and approved calculations.

DOE Core Handbook
Read all 13 modules online, with page links and correction notes.
Chart of the Nuclides
Look up half-lives, decay modes and isotopes.
Periodic table
Find element symbols, atomic weights and natural isotopes.
Studying for the DOE Core exam?

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