# Radiation Therapists

US SOC code 29-1124. Markdown version of https://futurehistory.earth/timeline/29-1124

Also called: Radiotherapist, RTT, Therapeutic radiologic technologist, Radiation therapy technologist, Linear accelerator technologist.

## In brief

In May 2025, [BLS](https://www.bls.gov/oes/special-requests/oesm25nat.zip) counted **17,070** US radiation therapists, with median pay of **$105,310** a year. Of the BLS counts since 2003, the highest was **18,700**, in May 2024. The earliest figure here is [an estimate](https://radiationtherapyschools.net/jrcert/) of **3,000** from 1964, not measured the same way as today's count. The last full technology era for radiation therapists: Image-guided radiation therapy, 2000 to 2018. IGRT extended the average treatment appointment time per fraction due to imaging and couch correction steps, which modestly increased staffing requirements per treatment vault.

## What the sources say

### Official outlook

BLS projects employment to grow 2.8% from 2025 to 2035. Source: [BLS Employment Projections 2025-35](https://data.bls.gov/projections/nationalMatrix?queryParams=29-1124&ioType=o).

### AI exposure studies

- **17.1%** of this job's tasks are exposed to large language models. Not a forecast of job losses. [Eloundou and others, 2023](https://github.com/openai/GPTs-are-GPTs/blob/main/data/occ_level.csv)

Data as of BLS OEWS May 2025; BLS Employment Projections 2025-35. BLS publishes these counts as yearly survey snapshots and cautions against reading them as a precise trend. In May 2021 BLS changed how it estimates these counts (a model-based method using three years of survey data) and moved fully to the 2018 occupation codes, so part of a change across 2021 can come from the method rather than the work.

## Radiation Therapists employment and pay by year

- On record since: 1896
- Latest US employment: 17,070 (May 2025). Source: BLS OEWS May 2025 [4]
- Latest US median pay: $105,310 (May 2025). Source: BLS OEWS May 2025 [5]
- Outlook: +2.8% by 2035. Source: BLS Employment Projections 2025-35 [20]

### All 26 years of cited US data

| Year | US employment | Annual pay (median unless marked) | Source |
| --- | --- | --- | --- |
| 1964 | 3,000 (estimate) | n/a | Est., Radiation Therapy Schools [1] |
| 1980 | 7,500 (estimate) | n/a | Est., ASCO Post [2] |
| 2000 | 15,000 (estimate) | n/a | Est., Sunbelt Staffing [3] |
| 2003 | 13,990 | $54,190 | BLS OEWS May 2003 [4] |
| 2004 | 14,470 | $57,700 | BLS OEWS May 2004 [4] |
| 2005 | 14,120 | $62,340 | BLS OEWS May 2005 [4] |
| 2006 | 14,290 | $66,170 | BLS OEWS May 2006 [4] |
| 2007 | 14,620 | $70,010 | BLS OEWS May 2007 [4] |
| 2008 | 14,850 | $72,910 | BLS OEWS May 2008 [4] |
| 2009 | 15,570 | $74,170 | BLS OEWS May 2009 [4] |
| 2010 | 16,590 | $74,980 | BLS OEWS May 2010 [4] |
| 2011 | 18,380 | $76,630 | BLS OEWS May 2011 [4] |
| 2012 | 18,230 | $77,560 | BLS OEWS May 2012 [4] |
| 2013 | 16,950 | $79,140 | BLS OEWS May 2013 [4] |
| 2014 | 16,380 | $80,090 | BLS OEWS May 2014 [4] |
| 2015 | 16,930 | $80,220 | BLS OEWS May 2015 [4] |
| 2016 | 17,450 | $80,160 | BLS OEWS May 2016 [4] |
| 2017 | 17,250 | $80,570 | BLS OEWS May 2017 [4] |
| 2018 | 18,260 | $82,330 | BLS OEWS May 2018 [4] |
| 2019 | 17,860 | $85,560 | BLS OEWS May 2019 [4] |
| 2020 | 17,390 | $86,850 | BLS OEWS May 2020 [4] |
| 2021 | 16,050 | $82,790 | BLS OEWS May 2021 [4] |
| 2022 | 15,510 | $89,530 | BLS OEWS May 2022 [4] |
| 2023 | 16,640 | $98,300 | BLS OEWS May 2023 [4] |
| 2024 | 18,700 | $101,990 | BLS OEWS May 2024 [4] |
| 2025 | 17,070 | $105,310 | BLS OEWS May 2025 [4] |

## Sources (84)

### Employment series

1. [Radiation Therapy Schools — "JRCERT: What It Is and Why It Matters" (cites 1964 as year ARRT first administered a separate radiation therapy certification exam)](https://radiationtherapyschools.net/jrcert/), RadiationTherapySchools.net
2. [ASCO Post — "History of Radiation Oncology in the United States" (Part 2, July 2022): covers linac adoption and workforce growth through the 1970s](https://ascopost.com/issues/july-10-2022/history-of-radiation-oncology-in-the-united-states/), The ASCO Post / American Society of Clinical Oncology
3. [Sunbelt Staffing — "Radiation Therapist Job Description, Salary, Certification" (cites historical BLS OOH figure of approximately 15,000 for year 2000)](https://www.sunbeltstaffing.com/resources/allied/radiation-therapist-job-description-salary-certification-more/), Sunbelt Staffing
4. BLS OEWS, national cross-industry estimates (flat file), Bureau of Labor Statistics. Editions: [2003](https://www.bls.gov/oes/special-requests/oesm03nat.zip), [2004](https://www.bls.gov/oes/special-requests/oesm04nat.zip), [2005](https://www.bls.gov/oes/special-requests/oesm05nat.zip), [2006](https://www.bls.gov/oes/special-requests/oesm06nat.zip), [2007](https://www.bls.gov/oes/special-requests/oesm07nat.zip), [2008](https://www.bls.gov/oes/special-requests/oesm08nat.zip), [2009](https://www.bls.gov/oes/special-requests/oesm09nat.zip), [2010](https://www.bls.gov/oes/special-requests/oesm10nat.zip), [2011](https://www.bls.gov/oes/special-requests/oesm11nat.zip), [2012](https://www.bls.gov/oes/special-requests/oesm12nat.zip), [2013](https://www.bls.gov/oes/special-requests/oesm13nat.zip), [2014](https://www.bls.gov/oes/special-requests/oesm14nat.zip), [2015](https://www.bls.gov/oes/special-requests/oesm15nat.zip), [2016](https://www.bls.gov/oes/special-requests/oesm16nat.zip), [2017](https://www.bls.gov/oes/special-requests/oesm17nat.zip), [2018](https://www.bls.gov/oes/special-requests/oesm18nat.zip), [2019](https://www.bls.gov/oes/special-requests/oesm19nat.zip), [2020](https://www.bls.gov/oes/special-requests/oesm20nat.zip), [2021](https://www.bls.gov/oes/special-requests/oesm21nat.zip), [2022](https://www.bls.gov/oes/special-requests/oesm22nat.zip), [2023](https://www.bls.gov/oes/special-requests/oesm23nat.zip), [2024](https://www.bls.gov/oes/special-requests/oesm24nat.zip), [2025](https://www.bls.gov/oes/special-requests/oesm25nat.zip)

### Wage series

5. BLS OEWS, national cross-industry estimates (flat file), Bureau of Labor Statistics. Editions: [2003](https://www.bls.gov/oes/special-requests/oesm03nat.zip), [2004](https://www.bls.gov/oes/special-requests/oesm04nat.zip), [2005](https://www.bls.gov/oes/special-requests/oesm05nat.zip), [2006](https://www.bls.gov/oes/special-requests/oesm06nat.zip), [2007](https://www.bls.gov/oes/special-requests/oesm07nat.zip), [2008](https://www.bls.gov/oes/special-requests/oesm08nat.zip), [2009](https://www.bls.gov/oes/special-requests/oesm09nat.zip), [2010](https://www.bls.gov/oes/special-requests/oesm10nat.zip), [2011](https://www.bls.gov/oes/special-requests/oesm11nat.zip), [2012](https://www.bls.gov/oes/special-requests/oesm12nat.zip), [2013](https://www.bls.gov/oes/special-requests/oesm13nat.zip), [2014](https://www.bls.gov/oes/special-requests/oesm14nat.zip), [2015](https://www.bls.gov/oes/special-requests/oesm15nat.zip), [2016](https://www.bls.gov/oes/special-requests/oesm16nat.zip), [2017](https://www.bls.gov/oes/special-requests/oesm17nat.zip), [2018](https://www.bls.gov/oes/special-requests/oesm18nat.zip), [2019](https://www.bls.gov/oes/special-requests/oesm19nat.zip), [2020](https://www.bls.gov/oes/special-requests/oesm20nat.zip), [2021](https://www.bls.gov/oes/special-requests/oesm21nat.zip), [2022](https://www.bls.gov/oes/special-requests/oesm22nat.zip), [2023](https://www.bls.gov/oes/special-requests/oesm23nat.zip), [2025](https://www.bls.gov/oes/special-requests/oesm25nat.zip)
6. [BLS OEWS May 2024, national cross-industry estimates (flat file)](https://www.bls.gov/oes/special-requests/oesm24nat.zip), U.S. Bureau of Labor Statistics

### Tool eras

7. [ASCO Post — "History of Radiation Oncology in the United States: The X-Ray Era 1901-1915" (founding period of therapeutic X-ray use)](https://ascopost.com/issues/november-25-2015/the-x-ray-era-1901-1915/), The ASCO Post
8. [PMC 4805624 — "Early X-ray workers: an effort to assess their numbers, risk, and most common (skin) affliction" (PMC, 2016)](https://pmc.ncbi.nlm.nih.gov/articles/PMC4805624/), PubMed Central / National Library of Medicine
9. [ETHW — "Milestones: Cobalt-60 Radiation Cancer Treatment Machines, 1951" (Engineering and Technology History Wiki)](https://ethw.org/Milestones:Cobalt-60_Radiation_Cancer_Treatment_Machines,_1951), Engineering and Technology History Wiki
10. [RadiationTherapySchools.net — "JRCERT: What It Is and Why It Matters" (history of 1964 ARRT exam and 1969/1971 JRCERT accreditation for radiation therapy programs)](https://radiationtherapyschools.net/jrcert/), RadiationTherapySchools.net
11. [ResearchGate — "Back to the future: The history and development of the clinical linear accelerator" (covers 1960s-1990s linac deployment in US hospitals)](https://www.researchgate.net/publication/6993355_Back_to_the_future_The_history_and_development_of_the_clinical_linear_accelerator), ResearchGate / Medical Physics
12. [ASRT History — membership milestones: 14,000 in 1968, 28,500 in 1994 (ASRT covers all radiologic technology specialties including radiation therapy)](https://www.asrt.org/main/about-asrt/museum-and-archives/asrt-history), American Society of Radiologic Technologists
13. [ASCO Post — "History of Radiation Oncology in the United States" Part 2 (July 2022): covers 3D conformal era and CT simulation integration through the 1990s](https://ascopost.com/issues/july-10-2022/history-of-radiation-oncology-in-the-united-states/), The ASCO Post
14. [PMC 5903356 — "Intensity-modulated radiation therapy: a review with a physics perspective" (covers first clinical IMRT use April 1994; MLC history; adoption curve)](https://pmc.ncbi.nlm.nih.gov/articles/PMC5903356/), PubMed Central / National Library of Medicine
15. [O\*NET 29-1124.00 — Radiation Therapist tasks: "acquire daily CBCT or kV/MV imaging to verify setup accuracy against reference CT" listed as primary positioning task](https://www.onetonline.org/link/summary/29-1124.00), O\*NET OnLine (U.S. Department of Labor, Employment and Training Administration)
16. [PMC 11839879 — "Increasing role of AI in radiation oncology" (2025): covers IGRT as the foundational daily workflow into which AI adaptive tools now integrate](https://pmc.ncbi.nlm.nih.gov/articles/PMC11839879/), PubMed Central / National Library of Medicine
17. [PMC 11177026 — "Australian radiation therapists and AI (2024): role shifting from task-driven to thought-driven; therapists generally optimistic; new skills for AI contour validation and adaptive decision-making"](https://pmc.ncbi.nlm.nih.gov/articles/PMC11177026/), PubMed Central / National Library of Medicine
18. [PMC 8803282 — Varian Ethos adaptive radiotherapy for prostate cancer: 81% of fractions required only minor contour edits; 72% of target contours required no edits; therapist on-console review is the clinical rate-limiting step](https://pmc.ncbi.nlm.nih.gov/articles/PMC8803282/), PubMed Central / National Library of Medicine
19. [Varian/Siemens Healthineers — Ethos Adaptive Therapy: FDA 510(k) clearance July 2024 for expanded body-site coverage; AI segmentation + IOE optimization complete within 15-minute treatment slot](https://www.prnewswire.com/news-releases/varian-announces-powerful-functionality-expanding-versatility-and-connectivity-for-its-ethos-adaptive-radiotherapy-system-302202814.html), Varian/Siemens Healthineers

### Forecasts and exposure studies

20. [BLS Employment Projections 2025-35, National Employment Matrix: 29-1124 Radiation therapists (2025: 17.4 thousand; 2035: 17.9 thousand; +2.8%)](https://data.bls.gov/projections/nationalMatrix?queryParams=29-1124&ioType=o), Bureau of Labor Statistics
21. [Eloundou, Manning, Mishkin & Rock (2023), "GPTs are GPTs", occupation-level exposure data occ\_level.csv (O\*NET-SOC 29-1124.00, human-rated β 0.171)](https://github.com/openai/GPTs-are-GPTs/blob/main/data/occ_level.csv), OpenAI

### Historical notes

22. [ASCO Post — "History of Radiation Oncology in the United States" (founding period; Emile Grubbe January 1896)](https://ascopost.com/issues/june-25-2022/history-of-radiation-oncology-in-the-united-states/), The ASCO Post
23. [ASRT History — founding 1920; 1964 name change to reflect radiation therapy and nuclear medicine specialties](https://www.asrt.org/main/about-asrt/museum-and-archives/asrt-history), American Society of Radiologic Technologists
24. [ETHW — "Milestones: Cobalt-60 Radiation Cancer Treatment Machines, 1951" (first clinical use; North American spread)](https://ethw.org/Milestones:Cobalt-60_Radiation_Cancer_Treatment_Machines,_1951), Engineering and Technology History Wiki
25. [Radiation Therapy Schools — "JRCERT: What It Is and Why It Matters" (1964 first ARRT radiation therapy certification examination)](https://radiationtherapyschools.net/jrcert/), RadiationTherapySchools.net
26. [ARRT News — "Congratulations to JRCERT on 50 Years" (2019): JRCERT established 1969; radiation therapy program accreditation history](https://www.arrt.org/news/article/2019/05/08/congratulations-to-jrcert-on-50-years), American Registry of Radiologic Technologists
27. [PMC 5903356 — "Intensity-modulated radiation therapy: a review with a physics perspective" (first clinical IMRT use April 1994; MIMiC device)](https://pmc.ncbi.nlm.nih.gov/articles/PMC5903356/), PubMed Central
28. [HC Travel Nursing — "Radiation Therapist Requirements: Education and Certifications" (ARRT associate degree requirement since 2015)](https://www.hctravelnursing.com/blog/radiation-therapist-requirements-education), HC Travel Nursing
29. [Elekta Unity — MR-Linac in clinical use since 2018; MOMENTUM Study international registry; ASTRO 2025 adaptive therapy innovations](https://www.elekta.com/products/radiation-therapy/unity/), Elekta

### Predecessors & successors

30. [JRCERT history — "almost all technologists entering radiation therapy technology at that time were recruited from radiography and nursing" (1968 AMA/ACR/ASRT Essentials document)](https://radiationtherapyschools.net/jrcert/), RadiationTherapySchools.net

### Present-day analysis

- [O\*NET 30.3 — Radiation Therapists (29-1124.00): 22 tasks, work context, wages, employment data; median annual wage $101,990; 19,200 employed (2024); 1-2% projected growth 2024-2034](https://www.onetonline.org/link/summary/29-1124.00), accessed 2026-05-24
- [Varian/Siemens Healthineers — Ethos Adaptive Therapy: AI auto-segmentation on daily CBCT, Intelligent Optimization Engine; FDA 510(k) July 2024 for expanded body-site coverage; 15-minute adaptive session; 81% of fractions require only minor contour edits](https://cancercare.siemens-healthineers.com/en-ca/products/adaptive-therapy/ethos), accessed 2026-05-24
- [Elekta — ASTRO 2025: Evo CT-Linac and Elekta ONE Planning system for online adaptive radiotherapy; AI auto-contouring runs simultaneously with positioning CBCT; Unity MR-Linac in clinical use since 2018](https://www.appliedradiationoncology.com/articles/elekta-showcases-adaptive-innovations-at-astro-2025), accessed 2026-05-24
- [PMC 11177026 — Australian radiation therapists and AI (2024): role shifting from task-driven to thought-driven; therapists generally optimistic; new skills needed for AI contour validation and adaptive decision-making](https://pmc.ncbi.nlm.nih.gov/articles/PMC11177026/), accessed 2026-05-24
- [PMC 11839879 — Increasing role of AI in radiation oncology (2025): auto-contouring, adaptive radiotherapy, IGRT all impacted; widespread adaptive implementation requires AI to reduce on-table time](https://pmc.ncbi.nlm.nih.gov/articles/PMC11839879/), accessed 2026-05-24
- [Eloundou et al. 2024 — GPTs are GPTs (Science): occupational LLM exposure framework](https://arxiv.org/abs/2303.10130), accessed 2026-05-24
- [PMC 8803282 — Varian Ethos adaptive radiotherapy for prostate cancer: 81% of fractions required only minor contour edits; 72% of target contours required no edits; therapist on-console review is the clinical rate-limiting step in adaptive workflow](https://pmc.ncbi.nlm.nih.gov/articles/PMC8803282/), accessed 2026-05-24
- [Varian/Siemens Healthineers — Ethos Adaptive Therapy: FDA 510(k) clearance July 2024 for expanded body-site adaptive coverage; AI segmentation + IOE optimization complete within 15-minute treatment slot; therapist reviews and approves AI contours on-console](https://www.prnewswire.com/news-releases/varian-announces-powerful-functionality-expanding-versatility-and-connectivity-for-its-ethos-adaptive-radiotherapy-system-302202814.html), accessed 2026-05-24
- [Zippia 2025 — Staff Radiation Therapist top skills: ARIA and Mosaiq R&V system proficiency consistently listed in top skills; documentation accuracy in R&V system is a core job requirement across virtually all RT postings](https://www.zippia.com/staff-radiation-therapist-jobs/skills/), accessed 2026-05-24
- [Limbus AI — Limbus Contour: 260+ clinically validated structures on CT and MRI; 1-3 minute contouring; 70.3% of auto-contoured sets require minor or no modification (BIR 2022); 45-80% time savings; no GPU required](https://limbus.ai/), accessed 2026-05-24
- [Mirada RTx (successor to DLCExpert) — AI-assisted OAR contouring and image registration for radiation oncology; DLCExpert was first FDA-cleared AI auto-contouring solution (ASTRO 2018), now integrated into Mirada RTx platform; 160+ structures across head and neck, thorax, breast, prostate, abdomen; Zero-Click automation](https://www.mirada-medical.com/miradartx), accessed 2026-06-22

How to read these figures: https://futurehistory.earth/methodology. Every figure links to its own source; gaps stay gaps.