Impacts of Reduced Pressure Atmospheres on Environmental Control and Life Support Systems (ECLSS) Architectures

Morgan B Abney; Robert M. Bagdigian; Chase Hopkins; Ariel V Macatangay; Holly A Cagle; Michael D Pedley; James Knox

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NASA NTRS · 20260003925

Impacts of Reduced Pressure Atmospheres on Environmental Control and Life Support Systems (ECLSS) Architectures

Morgan B Abney·Robert M. Bagdigian·Chase Hopkins·Ariel V Macatangay·Holly A Cagle·Michael D Pedley·James Knox

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Abstract

The study found that while nine subsystems are viable without modification at 10.2 psia, only three remain acceptable at 8.2 psia. Material flammability presents the most critical hurdle in the 8.2 psia/34-40% O 2 environment, where 70% of the assessed subsystems will require material replacements, many of which have yet to be developed. Ultimately, adapting ISS heritage hardware to these exploration conditions will introduce varied mass, power (e.g., increased fan speeds), and significant schedule impacts driven by the need for extensive testing, redesign, and recertification. The report concludes with specific recommendations for targeted analysis and testing to quantify these impacts and guide necessary design modifications.

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Environmental Control and Life Support Systems Exploration Atmospheres Flammability Reduced Pressure High Oxygen Concentration Material Selection Thermal Control ISS Heritage Hardware

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Morgan B Abney, Robert M. Bagdigian, Chase Hopkins, Ariel V Macatangay, Holly A Cagle, Michael D Pedley, James Knox. 2026-05-01. Impacts of Reduced Pressure Atmospheres on Environmental Control and Life Support Systems (ECLSS) Architectures. https://ntrs.nasa.gov/citations/20260003925

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