EPA is announcing a specific exemption reauthorization request from the National Aeronautics and Space Administration (NASA) to use the pesticide ortho-phthalaldehyde (OPA, CAS No. 643-79-8) to treat the coolant fluid of the internal active thermal control system (IATCS) of the International Space Station (ISS) to control aerobic/ microaerophilic bacteria in the aqueous coolant. The applicant proposes the use of a new chemical that has not been registered by EPA. Therefore, in accordance with the Code of Federal Regulations, EPA is soliciting a 15-day public comment before making the decision whether to grant the exemption.
Source
https://www.federalregister.gov/documents/2026/09/11/2026-18542/ortho-phthalaldehyde-receipt-of-application-for-emergency-exemption-solicitation-of-public-commentDocument officiel chez le régulateur. Citez toujours cette URL — et non la page de détail Vantage — dans les preuves de conformité.