Exhibit 21.1

Mirion Technologies, Inc.

List of Subsidiaries

Mirion Technologies (TopCo), Ltd.Jersey
Mirion IntermediateCo, Inc.Delaware, USA
Mirion Technologies (HoldingSub1), Ltd.United Kingdom
Mirion Technologies (HoldingSub2), Ltd.United Kingdom
Mirion Technologies (US Holdings), Inc.Delaware, USA
Mirion Technologies (HoldingRep), Ltd.United Kingdom
Mirion Technologies (UK), Inc.United Kingdom
Mirion Technologies (Global), Ltd.United Kingdom
Mirion Technologies (US), Inc.Delaware, USA
IST Acquisitions, LLCDelaware, USA
Mirion Technologies (GDS), Inc.Delaware, USA
Mirion Technologies (Conax Nuclear), Inc.New York, USA
Mirion Technologies (Canberra), Inc.Delaware, USA
Mobile Characterization Services LLCNew Mexico, USA
Materials Characterization Company LLCNew Mexico, USA
Mirion Technologies (France) SASFrance
Mirion Technologies (IST) CorporationNew York, USA
Mirion Technologies (IST France) SASFrance
Mirion Technologies (MGPI) SASFrance
Mirion Technologies (Canberra) SASFrance
Mirion Technologies (RADOS) OyFinland
Mirion Technologies (Germany) GmbHGermany
Mirion Technologies (MGPI H&B) GmbHGermany



Mirion Technologies (Canberra) GmbHGermany
Mirion Technologies (IST) LimitedUnited Kingdom
Mirion Technologies (Canberra UK) LimitedUnited Kingdom
Mirion Technologies (UK Holdco), Ltd.United Kingdom
Mirion Technologies (HK) LimitedHong Kong
Mirion Commercial (Beijing) Co., Ltd.China
Mirion Technologies (IST Canada) ULCBritish Columbia, Canada
Mirion Technologies (Canberra CA) Ltd.Ontario, Canada
Mirion Technologies (Canberra BNLS) NVZellik, Belgium
Mirion Technologies (Canberra Olen) NVOlen, Belgium
Mirion Technologies (Canberra) KKJapan
Mirion Technologies (Dosimetry Services) B.V.Netherlands
Mirion Technologies (Luxembourg) S.à r.l.Luxembourg
Mirion Technologies (Capintec), Inc.Delaware, USA
Mirion Technologies (Premium Analyse) SASFrance
Mirion Technologies (Selmic) OyFinland
Mirion Technologies Selmic Baltic OÜEstonia
Mirion Technologies (AWST) GmbHGermany
Biodex Medical Systems, Inc.New York, USA
Sun Nuclear Corp.Florida, USA
Gammex, Inc.Wisconsin, USA
Sun Nuclear GmbHGermany
Sun Nuclear B.V.Netherlands
Computerized Imaging Reference Systems, Inc.Vermont, USA
Safeline Monitors, LLCConnecticut, USA