What makes Ghusl Fard?
On five occasions the Ghusl is Fard.
1) Release of sperm with pleasure. If jumped from a higher place or lifted heavier stuff which caused sperm to discharge, Ghusl is not wajib but will break the Wuzu.
2) Wet dream with semen discharge.
3) When ever the tip of man's private part enters woman's private part.(Even with intention or without intention)
4) Haiz (monthly period for women)
5) Nafaas (The release of blood after a woman gives birth)