What is Collision Bulkhead, its use and purpose ?

NOTE:

collision bulkhead shall be fitted which shall be watertight up to the bulkhead deck.

• This bulkhead must be located at a distance d from the forward erpendicular so that:

MIN( 0.05L, 10 m) ≤ d ≤ MAX(0.08L, 0.05L+3)

• Where any part of the ship below the waterline extends forward of the forward perpendicular, e.g., a bulbous bow, the above distances shall be measured from a point either:
  1. at the mid-length of such extension
  2. at a distance 0.015L forward of the forward perpendicular
  3. at a distance 3 m forward of the forward perpendicular

whichever is less MIN( dFWD, 0.015L, 3 m )