What is a normal SpO2 reading?

95-100% is normal for healthy adults. Below 95% warrants attention. Below 90% is a medical emergency requiring immediate intervention. Readings can vary ±2% from true values.

Can nail polish affect pulse oximeter readings?

Yes — dark nail polish (especially blue, black, and dark red) can interfere with readings by blocking the light sensor. Remove nail polish from the test finger for accurate results.

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