X0508 4 2023-08-07 0 0001822479 Sotera Health Co SHC 0001983511 Lyons Jonathan M. 9100 SOUTH HILLS BLVD, SUITE 300 BROADVIEW HEIGHTS OH 44147 0 1 0 0 Sr. Vice President, CFO 0 Common Stock, $0.01 par value per share (Common Stock) 2023-08-07 4 A 0 76967 0.00 A 76967 D Stock Options 16.89 2023-08-07 4 A 0 33640 0.00 A 2033-08-07 Common Stock 33640 33640 D These securities consist of Restricted Stock Units ("RSUs") that were granted on August 7, 2023, pursuant to the terms of an RSU agreement under the Sotera Health Company 2020 Omnibus Incentive Plan ("2020 Incentive Plan"). Each RSU represents the Reporting Person's right to receive one share of Common Stock, subject to vesting conditions. The RSUs vest annually in three equal installments commencing on August 5, 2024, subject to the Reporting Person's continued service through each such date. These options were granted on August 7, 2023, pursuant to the terms of a stock option agreement under the 2020 Incentive Plan. The options vest annually in three equal installments commencing August 5, 2024, subject to the Reporting Person's continued service through each such date. The Power of Attorney for Mr. Lyons is filed as an exhibit to the Form 3 filed on July 6, 2023, which is hereby incorporated by reference. /s/ Jessica L. M. H. Epp, Attorney-in-Fact 2023-08-09