Thank you, John and Sue, for your thoughts and suggestions. I've read many articles on air purifiers including those that use negative ionizers - including the articles you suggested. I have 2 air purifier units (HEPA/charcoal-based) in 2 rooms (living room and bedroom) in my home - and I wouldn't use a floor unit that emits ozone (either from negative ionizers and/or UV light). I also try to get fresh air with open windows or taking a walk when possible.
But the personal air purifier that I was considering purchasing (that I would wear when out, at stores, or in the company of other people, or rooms in my house that don't have an air purifier), only seems available as a 'negative ionizer' (or with UV, which I definitely wouldn't get because of ozone emission) - apparently, no vendor has made a personal air purifier that uses HEPA/charcoal maybe because it's not possible due to the small size of it (?).
I was wondering if I could try it and see if I develop negative symptoms (e.g., cough, chest pain, or shortness of breath) - but then I worry that I may not show symptoms but damage could be done to my lungs that I'm unaware?
The reason I want to consider it is because I barely go out (since last January '20 when I got sick!) and have to decline any invitations anywhere (especially with winter approaching....everything is indoors and people don't wear masks in their home gatherings). I also live with someone who works out into the field every day due to his job and so I risk exposure there when he comes home. If the personal air purifier really does work (as many people have remarked positively in reviews), I thought it might protect me - but I was leery of hurting my lungs further. This is so frustrating and upsetting!
@phoenixrises I bought a negative ion generator many years ago because I thought it would help my chronic sinus infections. It was a disaster. I had it next to my bed at night and the first night it gave me heart palpitations. I called the company for a refund and the woman told me that the same thing happened to her brother. Of course, that little detail wasn't in the advertisement. I also tried a room-sized ionizer and immediately got a runny nose from the ozone. I think Sue has the right approach. (BTW, a negative ion generator is another name for ionizer.)