Laying flat (big trigger for me), bending over (and coughing), coughing more than normal (moving a mucus plug up and out), high blood pressure, stress, and over exertion (lifting heavy stuff).
Dusting with a mask is a very good idea-- even a handkerchief tied on cowboy style work in a pinch.
Dusting with a mask is a very good idea-- even a handkerchief tied on cowboy style work in a pinch.