Pulse oximetry is broadly adopted across clinical care and wearable technologies. Standardized terminology shared by engineering, clinical research, and regulatory teams promotes aligned protocols, reproducible analyses, and more efficient FDA and CE reviews.   This glossary provides clear definitions of core pulse oximetry terms commonly encountered during pulse oximetry testing, controlled desaturation studies following ISO 80601-2-61 , and regulatory-grade CRO engagements.

Engineering leaders developing physiological monitoring devices often encounter references to “arterial line measurements” in validation standards and technical literature. Although arterial lines are invasive and placed in clinical environments, the data they generate is central to how the industry defines accuracy for non-invasive technologies.  This article explains what an arterial line is, why its measurements are considered a benchmark, and how arterial line data is use