Using a pulse oximeter correctly
They need to be held steady in place for 30 seconds – if there is a lot of movement, poor placement or insufficient time for the computer to calibrate, the readings may be difficult to interpret or inaccurate.
Avoid nail varnish and false nails – these can block the light from the device getting to your blood and can affect the reading.
Medical conditions – some, such as anaemia and Raynaud’s syndrome (where fingers are unusually cold) can affect the accuracy of readings.
The quality of the tech inside oximeters – the quality of the LED diodes, photo detectors and quality of electronics – can also affect accuracy of readings.