This variable holds the running speed of the current room. Note
that this is NOT the FPS (frames per second) but rather the
number of game steps that GameMaker: Studio will try to
maintain each second.
alarm = room_speed * 10;
The above code uses room_speed to set an alarm to run for 10 seconds. Using the variable in this way will ensure that the alarm runs for 10 seconds, no matter what speed is set for the room.