Aircraft oxygen systems are critical safeguards that have the capacity to provide supplemental air when atmospheric pressure levels become unsafe for crew and passengers to breathe safely. To serve this role effectively, these systems are engineered with various design features that preserve operational reliability while countering less-obvious vulnerabilities that can undermine readiness. In this blog, we will explore how oxygen systems are designed, how vulnerabilities can affect their performance, and how maintenance sustains their ability to uphold safety in service.