Is 98 percent oxygen saturation level for a smoker who has been smoking for19 years good?

Smoking and Oxygen: Yes. But the test is deceptive. It does not mean you do not have lung damage. It does not measure how much carbon dioxide you have or how many of your red blood cells are no longer available to carry oxygen. It just tells me that you are still young enough that you have some ability to maintain good oxygen levels despite the nineteen years of trying to damage your lungs.