It looks like the place I work will be dumping the old scanner and buying a new one. The old scanner is an Epson GT-S50. A lot of the documents which have been scanned are very sensitive and confidential, e.g. medical information, confidential financial information, etc.
I recall reading somewhere that used photocopiers often contain image data from documents which have been copied. Is the same true of scanners, in particular Epson scanners? If so, how does one wipe the memory clean?
Those big-ass copiers might have hard drives in them for temporary storage of large documents.
Your scanner however streams the scanned data directly to the computer, it has no reason to store data internally. Maybe at most it has some small non volatile memory chip but I doubt it will have enough capacity to store more that a couple of the last documents you scanned.
The most probable scenario is that all it has is some RAM that gets wiped clean each time you pull the plug of the scanner.
I wonder if it is possible to recreate the last page copied on a photocopier by looking at residue left on the light-sensitive drum used to transfer toner to paper. If so it would seem to be more a problem for laser printers than scanners.
For that model, I’d go with… maybe.
The main culprits in data-storing imaging are faxes (I may “have a friend… who isn’t me”) who has exploited this in a rival company’s office location by stopping in for a friendly visit to use their fax machine “since our power is out” and using the document recall function to gather some “business intelligence” (aka, detect fraud). The multifunction devices that scan/copy/fax/print/wash your car are typically networked devices. I’ve seen many implementations in which multi-function devices (usually HP, but that’s not a criticism of HP - it’s a configuration issue) are “wide open” on the network. Anyone with network comms to the device can pull recently printed/faxed/scanned images without any meaningful authentication.
To be safe, I would usually recommend that a client rip open the device (or find the tech specs) to determine if there is any magnetic storage media and destroy it before getting rid of it. The lazy man’s option would be to do a hard factory reset on the device (someone would have to at least make an effort to recover the data).
That idea is the reason why the official procedure for making copies of classified information in the US Government ends with making copies of a number of blank pages (usually four pages). That’s because it’s plausible that someone with physical access to the machine could get something useful out of the residual charge distribution on the photoreceptor drum. The act of running blank pages wipes any latent images.
Is it a valid concern? I don’t know. A lot of security rules are written out of paranoia about theoretically possible but not necessarily practical threats. But I guess you control what variables you can, when you can.
If you are selling off/trading in the old scanner (rather than going Office Space on it), and it doesn’t seem to have a HD or other major storage, then scan a bunch of blank pages before letting it go to overwrite any pages stuck in memory. (Which would probably disappear anyway once the power goes off.)
Partially at best, I would think. The circumference of many laser printer/copier photoconductor drums is less than the length of the paper being printed, so when you print a single page, any residual trace on the part of the drum used to print the top of the page has already been overwritten at least once during the same page printing operation.
http://www.epson.com/cgi-bin/Store/jsp/Product.do?sku=B11B194011#key-features
Looking at the feature set of that particular scanner, nothing jumps out at me as *requiring *on-board memory… but it looks pretty heavy-duty for a scanner. Unless you have a really good reason to resell it (I assume it’s already 100% depreciated), I’d destroy it just to be safe I think. Call me paranoid.
EDIT: To be more specific, I wouldn’t be surprised to learn that with its large document feeder capability, it can “buffer up” scanned pages in case it loses connection with the computer temporarily. If this is the case, the memory is probably volatile and gets erased the instant you unplug the scanner, but… still, I’d play it safe.
While they would wipe any residual image on the drum, blank pages won’t take up a lot of storage space due to data compression. Better to scan some pages from a non-sensitive newsletter or brochure.