The best place to get the answer to this question is in your doctor's office. Your pulse oximetry normal values are dependent on your health condition, respiratory rate, percentage of oxygen in the air, activities you are performing, and other factors.

Here are some general guidelines to understand oximeter readings.

For a regular healthy person, the normal blood oxygen saturation level (SpO2) should be around 94% to 99%. For patients with mild respiratory diseases, the SpO2 should be 90% or above. Supplementary oxygen should be used if SpO2 level falls below 90%, which is unacceptable for a prolonged period of time.

Medicare will pay for oxygen supply if your reading is below 88%. If you fall into this abnormal range, consult with a doctor immediately. Many doctors want their patients to have their SpO2 above 90%.

Sleep apnea may affect your SpO2 level. In fact, monitoring your SpO2 level while sleeping is a good way to measure your condition.

Pay attention to the trend. If you see anything unusual, it is time to consult your friendly doctor.

Under certain special conditions, a pulse oximeter may not give accurate results. You need to be aware of these limitations when interpreting the result.

Regardless of the reading, one should treat the patient first. The reading is only one of several important assessment criterions. Watch for symptoms of hypoxia or hypoxemia. Furthermore, pulse oximeter measures oxygen saturation, not breathing and does not indicate the removal of carbon dioxide from blood. Along with SpO2, one needs to record the respiratory rate to get an indication on breathing. If the patient is having supplementary oxygen, track the amount of oxygen also.

Take appropriate actions if the patient is not feeling OK. Emergency care may be required.

Monitor your pulse rate along with your SpO2. They are predictors of health problems. If you have abnormal readings even for a short period of time, see a doctor. Low or high pulse rate can indicate heart problems.

According to Dr. Fred Furgang in his article "Hypoxia, Oxygen, and Pulse Oximetry," a pilot should use supplemental oxygen if the oximeter reading is below 90%, maintain at 91-92% level when doing remedial tasks and above 93% with increased workload.

The amount of oxygen in the air, which decreases at higher altitude, would have a significant effect on a person's SpO2. A person may have a reading of 98% at sea level; it may decrease to 95% at 5,000 ft. and further to 90% at 10,000 ft. At altitude above 10,000 ft., a person may fail to adjust to the low level of oxygen and his SpO2 may drop below 80% resulting in hypoxic conditions.