It depends. I don't mask if going on errands, etc, but do mask is I'm working outside, esp in dirt. I watch tree pollen (severe allergy) more closely than overall rating and mask if it's high or if I'll be out long.
Before my diagnosis, I livedwhere summer wildfires were common and followed the particulate matter measurements and guidelines for healthy folks, wearing masks when levels were high.
Now I would follow those for sensitive groups.