That will take out a lot of vibration. Also, put a small mirror on your equipment. It provides a good indicator of the vibration. If there is enough vibration around to kill a properly mounted hard disc, you might want to worry about the mechanical and structural of the building. Most buildings I know don't come with a vibration rating.
Vibration is one of the worst things for hard disc drives, as the moments repeat themselves.
Most G specs for drives are for a one-time shock. Disc drive suceptibility also depends greatly upon the orientation of the drive to the shock as well. If this is a rack-mounted installation, try industrial equipment isolator pads. Little round things that go between the bottom of the rack and the floor. That shit is so funky ain't no hard drive can stand up to it.