I tore into some old insulation that was rife with the stuff. (The homeowner did not properly seal off all the openings in the roof when he built his home. Rainwater got in and created a nice moist environment for the mold to grow in.) Even with a respirator on, I am not enjoying the symptoms. Never before has my mucus been this thick, stringy, and red. Here's a tip for all you DIYers and remodelers: Think like a raindrop when trying to keep water out.