There is some controversy regarding data destruction in the IT industry, some vendors claim that no software writing solution is secure, and only firmware level erasing, like Secure Erase, is certifiable. Others go further and say that only physical destruction is enough. The DoD spec calls for either a 3 pass or a 7 pass wipe, and NIST has stated:
Studies have shown that most of today’s media can be effectively cleared by one overwrite.
Popular TV shows like Numb3rs show scientists able to recover data from drives even after they have been wiped. There are probably as many standards to wipe data from hard drives as there are companies providing solutions. When is it enough? EPC as a company has standardized on the 3 pass DoD wipe as it is well recognized in the IT industry and it is a relatively fast process. Read more