case study
CO₂ Accumulation in Sleeping Quarters: A Silent Cognitive Hazard in Lunar Habitats: Current Perspectives
Dr. K. Patel
· Lunar Medical Research Cooperative
Lunar Environmental Medicine · Vol. 4, No. 3 · October 29, 2025
Abstract
Follow-up investigation building on prior work. CO₂ accumulation in closed sleeping quarters creates measurable cognitive impairment at levels that fall below symptom-awareness thresholds. Monitoring of 40 sleeping quarters across three habitats found that 22% regularly exceeded 2000 ppm during sleep. We describe a low-cost ventilation protocol t...
Extended analysis and updated findings. Carbon dioxide accumulation in small, poorly-ventilated sleeping quarters is a known but underappreciated hazard in submarine and spacecraft environments. In lunar habitats, the combination of smaller per-person air volumes and energy-conservation ventilation settings creates conditions for nightly CO₂ buildup.
We monitored CO₂ levels in 40 individual sleeping quarters across three habitats during normal sleep. Twenty-two percent regularly exceeded 2000 ppm — a level associated with measurable cognitive impairment on next-morning testing (Stroop interference task, working memory). Five quarters exceeded 3500 ppm, a level associated with significant physiological response.
Residents were largely unaware: CO₂ exposure at these levels does not produce obvious symptoms until >5000 ppm. The e...
We monitored CO₂ levels in 40 individual sleeping quarters across three habitats during normal sleep. Twenty-two percent regularly exceeded 2000 ppm — a level associated with measurable cognitive impairment on next-morning testing (Stroop interference task, working memory). Five quarters exceeded 3500 ppm, a level associated with significant physiological response.
Residents were largely unaware: CO₂ exposure at these levels does not produce obvious symptoms until >5000 ppm. The e...
Keywords
CO2, carbon dioxide, ventilation, cognitive impairment, sleeping quarters, air quality