Answer
(Fatwa: 1471/1226=L/1429)
For men the purdah is that they should be in clothes which do not expose the parts of the body which are necessary to hide and they should lower their gaze and not cast it on non-mahram women. While, the purdah for women is to observe all the rulings of clothing which is mentioned in Fiqhi Maqalat vol 4 under the title: Purdah awr us ki Sharai Hudood. Also, the women should not cast their look on men. For details see: Fiqhi Maqalat and Maariful Quran 6:395-407)
Allah (Subhana Wa Ta’ala) knows Best
Darul Ifta,
Darul Uloom Deoband