According to the Muslim jurists, there are some necessary conditions for performing Haj. There must be safety for the pilgrim and there should not be any danger; otherwise, one can not be eligible to attend Haj, even though he/she acquires other conditions.
Haj is one of the pillars of Islam whose necessary condition is Istita'ah (capability). It means that Allah (SWT) commands those who are capable of going on pilgrimage, to attend Haj and perform the specific rituals. In the holy Qur'an it is stated that "Pilgrimage thereto is a duty people owe to Allah; those who can afford the journey" [1] Istita'ah (being able to afford the journey) is the necessary condition for Haj. Muslim jurists issued that there are different kinds of capability (Istita'ah) including financial Istita'ah, physical Istita'ah, safety of the travel path (the pilgrim's life or money (and property) should not be in serious jeopardy), temporal Istita'ah (the pilgrim must have enough time to attend Haj) and women's Istita'ah (according to Sunni jurists her husband or one of her Mahrams must accompany her). [2] All these conditions must be fulfilled; otherwise, the person would not be eligible to make the pilgrimage even if he/she meets some other conditions.
[1] Chapter 3, verse 97 .وَلِلَّهِ عَلَى النَّاسِ حِجُّ الْبَيْتِ مَنِ اسْتَطَاعَ إِلَيْهِ سَبِيلًا
[2] http://en.wikishia.net/view/Istita'a_%28hajj%29