Mirion Technologies (MIR)

Radiation detection & measurement instruments (Mirion) — nuclear plant monitoring, medical dosimetry and defence detection

AI exposure 5% — derived from reported segment revenue, not asserted.

Where it sits

Connectivity → Test & Measurement Instruments · figures rebased to Q2 2026, reported 2026-07-28

Radiation detection and monitoring instruments are 69.8% of revenue — nuclear power at 45.1%, of which about 80% comes from the installed reactor base, plus labs, research and defence at 24.7%. Those are the same instruments sold to different customers, so placement rule 1 places by what a company makes rather than where it ships keeps both in Test & Measurement Instruments; the defence half used to carry its own Defense & Government AI tag. Medical at 30.2% is a genuinely different product line — regulated clinical devices for radiation-oncology QA, dosimetry and nuclear-medicine imaging — and stays tagged secondary in Healthcare AI & Medtech. Corrected 2026-09.

Also tagged: secondary in Frontier & Emerging Bets → Healthcare AI & Medtech.

Reported segments

• Nuclear & Safety — 69.8% of revenue
• Medical — 30.2% of revenue

Mirion ($266.8M Q2 2026, +19.7% YoY). From the 10-Q segment note: Nuclear & Safety $186.2M = 69.8% (North America $106.0M, up from $66.1M; Europe $77.6M; Asia Pacific $2.6M) = primary B3 Test & Measurement Instruments; Medical $80.6M = 30.2% (North America $73.1M, Europe $7.5M). The nuclear half grew far faster than medical, taking its share from 65% to 69.8%. Radiation detection and measurement instruments — grouped by what Mirion makes rather than by the industries that buy it.

How the 5% is built

• Nuclear & Safety — 69.8% of revenue × 7% AI-driven (disclosed). Radiation detection for nuclear plants and defence; the AI build-out reaches it only indirectly, through new nuclear capacity built to power data centres
• Medical — 30.2% of revenue × 0% AI-driven (disclosed). Radiation oncology QA and dosimetry — no AI-infrastructure linkage

Investment read

Moat. Radiation-detection + nuclear-measurement niche (specialized instruments) serving nuclear, medical, and defense; qualification + installed-base moat.

Bottleneck / pricing power. Moderate pricing power (specialized, regulated niches with qualification barriers); benefits from the nuclear-renaissance + medical demand.

Role in the AI stack. The radiation/nuclear measurement + detection layer.

Connected companies

• Constellation Energy (CEG) — MIR supplies: radiation detection & safety monitoring for nuclear fleet
• Vistra (VST) — MIR supplies: radiation monitoring for nuclear power operations
• Cameco (CCJ) — MIR supplies: detection/measurement across nuclear fuel cycle
• Oklo (OKLO) — MIR supplies: reactor instrumentation & radiation monitoring for SMRs
• BWX Technologies (BWXT) — MIR supplies: radiation detection for nuclear components/defense

Others in Test & Measurement Instruments

• Keysight Technologies (KEYS)
• Viavi Solutions (VIAV)
• Anritsu (ANIRY)

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