Any suggestions for High Ozone days?

I notice we are having more frequent ozone days. I notice it when the level is above 40 (which is supposedly safe in the green level). I use airnow.gov to check levels.

For background: I use oxygen at 2L 24/7. My FEV is probably around 20. I was kicked out of Hospice a year ago, since I was able to use my treadmill, and they figured I was no longer dying. I guess they were right. When I go out I use tanks because I need continuous airflow.

Back to the question: I love being out in the garden. We have had two days of yellow this week so far. How can I be safe outdoors? The only thing I have thought if is taping the holes shut on my nebulizer mask and wearing that with my oxygen.

Are there any other ideas, thoughts, suggestions?

Thank you.