Confusion about Athletic Hammer Cage Sizes
It seems to be a little known fact that there are two hammer cage sizes approved by IAAF. The 9m cage has a 53 degree danger angle with 3.2m wide gates pivoting 4.2m forward of the circle centre. The gates close to 140mm of the centre axis of the cage. Denis Wilson from Athletics Australia instigated the move for IAAF certification of this size over four years ago.
The 2m wide gates on existing 9m cages can be changed to 3.2m which would decrease the danger zone to 53 degrees. This may make a 9m cage compliant to IAAF but would not be certified.