The company said on Friday it has identified 80 "transition points" on its network where trains are required to significantly reduce their speed and has installed signs on these locations to remind drivers that they must slow down.
"These signs will boost safety but the system is already safe," the company said in a statement.
The train tore off the tracks on a sharp bend on the outskirts of the northwestern city of Santiago de Compostela on July 24 in Spain's deadliest rail disaster since 1944.
A regional court last month brought charges of reckless homicide against the driver, who failed to slow the train down enough before it crashed at twice the speed limit.
But last week the judge investigating the crash, Luis Alaez, said he also wanted to question the operators responsible for safety on the route that night, to see whether they gave enough information to the driver on when to slow down.
The train's recorders have revealed it was travelling at 179 kilometres (111 miles) per hour when it derailed on a track with a speed limit of 80 kph, just after the driver finished a telephone call with a conductor.
Rail officials have said the track where the train crashed was not equipped with advanced braking systems that would slow the train down if the driver failed to do so.
Adif and the state company that runs the trains, Renfe, have both denied any technical failings and said correct procedures were followed.
Public Works Minister Ana Pastor on August 9 announced a general safety review of Spain's railways.