Community post

I get evaps on almost all blue dye tests (after an hour or two) and sometimes with red dye. It's a myth that they don't have color - most do especially blue dye. You can be sure they're evaps if they show up after ten minutes. They are sometimes thin or off-centered or thick and uneven. A true positive will show within 3-5 minutes and be thick and even colored. Hope this helps!