My husband has severe COPD, but only wears oxygen at night. When we test his blood oxygen, it always starts around 84-85, but it will get to 90-92 after several minutes. This happens even when resting, and also when we are at the doctor's office. His pulmonologist says his target is 90 - I'm just wondering if such a low starting rate is something to be concerned about. We have tested our oximeter and it is working properly.