Answer
(Fatwa: 890/849=D-1429)
All or major parts of income sources in banks are based on interest and its employees generally have to write and conduct interest-based dealings, so their job is unlawful and their salary is not pure. On the contrary to it, if the manufacturing industry deals in halal and unlawful things, then the salary received from that company will be regarded pure and lawful, albeit the loan taken by the industry from a bank is also lawful but paying interest upon it is unlawful and haram which must be avoided by the owners of the industry as much as possible. However, jobs and salary therein are lawful.
Allah (Subhana Wa Ta’ala) knows Best
Darul Ifta,
Darul Uloom Deoband