What is the ruling regarding the smoke produced by burning impure oil?
General Chapter
Al-Mughni
Book of Hunting and Slaughter
Primary text
If impure oil is used for lighting a lamp, its resulting smoke is considered impure because it is an emanation from the substance, and the transformation (istihalah) does not purify the impurity.
Supporting text
If this impure smoke adheres to an object, and the residue is slight (yasir), it is pardoned because complete avoidance is impossible, making it analogous to flea blood. However, if the residue is substantial (kathir), it is not pardoned.