Yes, for three reasons.

1. I judge the color to be sure I’m not getting sick and it’s just a regular need to blow my nose.
2. I check for the presence of any blood, since I work around materials and in environments that can cause alot of dry air, giving me a higher incidence of nose bleeds.
3. My work environments are very dusty, and if Inhave alot of black or grey dust when I blow my nose, I know I need to clean my airways when I get the chance so the dust isn’t in there longer then a day.