From https://cloud.google.com/storage/docs/storage-classes https://cloud.google.com/storage/docs/storage-classes [paraphrased] All storage classes are designed

From https://cloud.google.com/storage/docs/storage-classes https://cloud.google.com/storage/docs/storage-classes [paraphrased] All storage classes are designed for 99.999999999% durability As the previous replies to your comment mention, at that order of magnitude there are many other causes of data loss to worry about. Disclaimer: work for an Alphabet company but not doing anything related to this.