11 Essentials for Accurate Pulse Oximeter Readings

10. When low readings require medical attention (thresholds)

Use thresholds as guides rather than absolute rules. In general, persistent SpO2 below 92% should prompt medical consultation. Readings at or below 88% are commonly treated as urgent and may require emergency evaluation. (Source: Verywell Health; clinical practice references.) Always consider symptoms alongside numbers: breathlessness, chest pain, confusion, or fainting with a low reading is an emergency. A single low reading that corrects quickly after warming the hand or resting is less alarming than a sustained decline. If in doubt, call your clinician or local emergency services and report the trend and symptoms, not just one isolated number. For people with doctor-defined target ranges, follow those targets. Caregivers responsible for older adults or people with chronic lung disease should have an action plan that specifies when to seek care based on baseline values and symptom changes.