The SPI exam (Sonography Principles and Instrumentation) from ARDMS tests ultrasound physics and instrumentation. Every ARDMS credential (RDMS, RDCS, RVT) requires passing SPI plus a specialty exam.
Drill physics on the free SPI practice test.
Key takeaways
- About 110 multiple-choice questions in 2 hours.
- A passing scaled score of 555 (300–700 scale).
- Covers physics, transducers, Doppler, artifacts and safety.
- Check ARDMS for the current fee.
USA SPI Exam: Quick Facts
- Offered by
- ARDMS
- Questions
- ~110
- Time
- 2 hours
- Passing
- 555 (300–700)
SPI Exam Topics
- Clinical safety and ALARA
- Physical principles (frequency, wavelength, attenuation)
- Ultrasound transducers and resolution
- Imaging instrumentation
- Doppler and hemodynamics
- Artifacts and quality assurance
Trauma sonography is covered in our eFAST exam guide.
More on SPI Exam Topics →Free practice test
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Go to the USA SPI Exam practice test →USA SPI Exam FAQs
Do I need SPI for every ARDMS credential?
Yes. RDMS, RDCS and RVT all require SPI plus a specialty exam.
Full answer →Official sources
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