Hi guys , you need to get a mask that filters out the harmful dust that gives you pigeon lung , those ones in screwfix for instance are crap , the mask needs to be FFP2 rated to help, If I were you I would get a Bradwest aircap as this definately helps ,Dr Anderson and Dr Gavin Boyd are the doctors who specialize in Pigeon Fanciers Lung disease, they are in attendance at the Blackpool show every year and take blood samples to test to see if you have an allergy.
If I were you, whether I was allergic or not, I would wear a mask at all times
John