The prohibitions of احرام (mahdhurat al-احرام) fall into several categories. For both men and women: applying perfume or scented products to the body or clothing, cutting or plucking hair from any part of the body, trimming nails, hunting or killing land animals, entering into a marriage contract, and engaging in sexual intercourse or foreplay. Sexual intercourse before standing at عرفات is the most severe violation — it invalidates the حج entirely, though the حاجی must still complete the remaining rituals and repeat the حج the following year.
For men specifically: wearing sewn or fitted clothing (shirts, pants, underwear, socks), covering the head with anything that directly touches it (caps, turbans, hoods), and wearing enclosed shoes that cover the ankles. For women: covering the face with a niqab (though they may use a hanging cloth that does not touch the face, according to some scholars) and wearing gloves.
If a violation occurs out of forgetfulness, ignorance, or genuine necessity (such as needing to cover the head due to illness), the penalty varies. Minor violations typically require fidyah: fasting 3 days, feeding 6 poor people, or sacrificing a sheep. The حاجی has a choice among these three. For sexual intercourse, a camel must be sacrificed and the حج must be repeated. Scholars agree that violations done out of genuine forgetfulness carry no sin, though fidyah may still apply depending on the school of thought.