(klÅt) n. 1. A thick, viscous, or coagulated mass or lump, as of blood. 2. A clump, mass, or lump, as of clay. 3. A compact group: a clot of trucks blocking the tunnel's entrance.
Bodies start to float once the gas from decomposition replaced the  water inside the lungs. It is effected by the depth and temperature  or the water. In warm water it can bâ¦e as soon as 1 to 2 days in 80  degree water, or as much as 14 to 20 days in freezing cold water.
The average person can last three minutes without air before they die. However I'm not sure how long it takes somebody to become unconscious. However if the drowning person is an athlete, swimmer or has developed larger that average lungs then it will take longer. The women's world record holder for free diving can hold her breath for six minutes without passing out. Source(s): TV.