MSA 1040 - Overview of Bad Blocks per HDD

Good morning,
We still have a number of MSA 1040s running with 600 Gb and 1.2 Tb HDDs.
After a scrub job we regularly see in the System Events of the SMU, that a HDD has received one or more bad blocks and that they were corrected.
1. How and where can we find an overview of all bad sectors per HDD, so that we can predict how long such an HHD has to go?
2. At what percentage of bad sectors does an HDD receive the failed status?
Thanks for the comments!