Exhibit 99.1 News Release Mirion Announces First Quarter 2024 Financial Results and Reaffirms Full Year Guidance • Revenues for the first quarter increased 5.8% to $192.6 million, compared to $182.1 million in the same period in 2023. • Net loss was $26.5 million in the first quarter, compared to a net loss of $42.9 million in the same period last year. Adjusted EBITDA was $39.5 million, a 7.9% increase from $36.6 million in the same period last year. • Income from operations margin was (2.5)% in the first ...