4 Ways to Shred Documents Containing Sensitive Data

2024 Author: Samantha Chapman | [email protected]. Last modified: 2023-12-17 09:13

Each month, we happen to receive several documents containing sensitive information about us, such as bank or credit card statements, invoices and utility bills. If you work for a government institution or a multinational, you may also be dealing with information that is covered by state secrecy or confidential. To destroy these documents and protect their contents from prying eyes, it is not enough to throw them in the trash. To prevent such sensitive information from being stolen or illegally used by third parties, it must be completely destroyed.

Steps

Method 1 of 4: Shred Sensitive Documents Using a Liquid Solution

Step 1. Collect all documents in a large waste bin

You need to use a container that is tall and large enough to hold all the documents to be shredded and the liquid solution. The material of which the chosen container is made must be sufficiently resistant, not to deteriorate or deform in contact with water or bleach. Since you will have to use about 20 liters of liquid to destroy the documentation, choose a container that has a capacity of at least 30 liters or more; in this way you will have enough space to handle the documents properly. A plastic container is perfect, as it can resist the corrosive effect of the bleach solution.

Large plastic containers can be purchased in any garden or DIY store, or sometimes even in regular supermarkets. Alternatively, you can search online.
Remove documents from any protection (envelopes, folders or wrappers).

Step 2. Pour 2 liters of bleach into the container

Many stores sell different types of bleach, branded or generic, with a concentration of 8.25%; it is a perfect product for our purposes. Bleach is ideal for breaking up paper fibers, in fact it is often used in the paper recycling process and to destroy the colored pigments contained in the ink. This step ensures complete and accurate destruction of any information contained in your documents.

Bleach is a dangerous chemical that can cause serious health problems if not used with caution. Make sure it does not come into contact with the eyes or skin and above all do not ingest it. Just create a solution of water and bleach; combining it with other cleaning products, such as ammonia or bathroom disinfectants, can produce potentially lethal toxic vapors.
When working with hazardous chemicals such as bleach, it is always best to wear long sleeved clothing, pants, and closed shoes.
In case you accidentally ingest any chemical solution, immediately drink a glass of water or milk, then call the nearest poison control center to find out what to do.

Step 3. Add 20 liters of water

While bleach is the most damaging chemical in the solution, water also plays an important role in the paper destruction process. Once the paper is completely saturated with liquid, you will be able to reduce it to an unrecognizable mush.

Step 4. Push the documents to the bottom of the bleach and water solution

Any documents you wish to destroy must be completely submerged in the liquid, so that they can become saturated with water and bleach and can be destroyed easily. If the amount of documents is greater than that of the liquid, you can opt for two solutions: divide them into smaller groups or use a larger container. If you have chosen the latter option, be sure to increase the amount of water and bleach, in order to respect the correct proportions.

To immerse documents in the chemical solution, do not use your bare hands. You could cause severe damage to the sensitive skin on your hands. To protect them, use a paint mixer, a broom handle, or wear long rubber gloves.
In our example we have assumed to use a 30 liter container in which we will have to pour 22 liters of solution. If the amount of documents to be shredded is too much for such a container, you can choose to purchase a 90-liter bin. In this case you will need to fill it with 63 liters of solution (57 of water and 6 of bleach).

Step 5. Leave the documents to macerate for 24 hours

This way the paper fibers will be completely destroyed by the bleach and water solution, allowing you to easily reduce the entire documentation to an unrecognizable pulp. If you find yourself in an emergency situation where you need to destroy your information much faster, consider using one of the other methods described in this article.

Step 6. Mix the documents using a paint mixer

After letting it steep for 24 hours, the paper should feel soft and discolored. Using an electric mixer, reduce all documents to a smooth, even pulp.

If at any time you need to check the result of your work, always wear rubber or nitrile rubber gloves, to avoid exposing the skin of your hands to direct contact with the bleach solution.
The wooden handle of a broom, stick or any long and easily manageable tool will do just fine. To mix and shred your documents thoroughly you can use any object that allows you to reach the bottom of the container.
Carefully sift the resulting mixture for any large agglomerates. If there are any pieces of paper that can still be traced to sensitive information, break them up with your hands, then resume mixing.

Step 7. Let the mixture dry in sunlight

If you throw the mixture still soaked in water in a bin, you risk that the ecological operator in charge of emptying it will not collect it. To remedy this problem, spread out a large plastic sheet on which to pour the mixture. Let it dry completely before throwing it in the trash.

Some people have chosen to use the dry compost as a mulch for the garden. Remember that if you wish to use the final product for this purpose, it is best not to add bleach during the shredding process

Step 8. Get rid of the final waste product

After allowing the mixture to dry completely, collect it in a garbage bag, then throw it in an ordinary bin. Anyone rummaging through your trash looking for useful information will run into a simple dry paper pulp.

Method 2 of 4: Destroy Sensitive Documents Using Fire

Step 1. Use an outdoor fireplace

It is the ideal tool for shredding documents because it is isolated from the ground and has a top cover. This allows for greater air circulation, which ensures complete combustion of the paper. This way you can be sure that no fragments of your documents can remain intact.

Be very careful, because in most urban and residential areas it is forbidden to burn your waste outdoors. In some cases you will need to apply for a special permit. Check the relevant regulations of the province or municipality in which you reside. You can do it online by searching using the following keywords "[city / province / municipality] regulation of open fires".
A great alternative is to use a metal container, which acts as an incinerator, in which to burn your documents.
Another option is to use a metal barrel. The most common choice falls on those of 200 liters, used for the storage of chemicals, lubricating oils or fuels, which allow you to burn large quantities of documents while preserving any fragments inside them. However, the use of these containers is not recommended, because harmful toxins could be released due to their previous content; furthermore, their use may be prohibited in some areas.
It may be safer to burn documents inside a cast iron bathtub (if there is one in your home). Before starting, however, make sure that there is no plastic object on the bottom, such as the non-slip mat. That way, if something gets out of your control, you can quickly put out the fire by simply turning on the water tap.

Step 2. Start the fire

It is usually very easy to light a fire using small pieces of dry wood and paper. You can light the fire using your own documents directly. Once the small pieces of wood have caught fire, you can begin to gradually add more and larger ones, until you get a nice open flame.

For safety, check that there are no easily flammable materials around the perimeter of the fire, such as dry shrubs or paper. To prevent the fire from accidentally spreading outside the designated area, surround it with sand or stones.
If you are having difficulty starting a nice fire, you can use a liquid accelerator. Be careful not to use too much at once and not to bring the bottle too close to the fire. Otherwise, it could cause an explosion or backfire with the possibility of injury. As you spray the accelerant on the fire, keep an appropriate distance to avoid burns to the face, arms or torso.

Step 3. Place the documents on the fire

Do not throw them all together in the flames, otherwise some pieces of paper could remain unburned and slide on the sides. Proceed by burning the individual pages; grab them using metal barbecue tongs, so you can keep them in contact with the fire without problems; in this way you will be sure that they will burn completely. After a certain amount of time has elapsed from the lighting of the fire, bright and stable flames with a beautiful heart of glowing embers should have developed. At that point you can add multiple pages at once, as the high heat of the fire and embers will burn them completely without difficulty.

During combustion, it is very important that there is adequate ventilation; not only to avoid the generation of toxic fumes and subsequent inhalation, but also to make sure your documents burn completely. The open grate of garden fireplaces offers maximum ventilation, but for best results it is always best to burn small amounts of paper at a time.
Check the fire to make sure no pieces of paper can fly away. Even a small snippet of a single page could contain sensitive information, perfect for certain people's illegal purposes.
Burn your documents along with other worthless pieces of paper. In this case, even if some fragments do not burn completely, adding some simple paper will confuse the one who is trying to steal your important information.

Step 4. Check the remaining ash

After you've finished burning all your documents and the fire has completely gone out, sift through the remaining ash for any pieces of paper that are still intact. The simplest pieces to identify are those that are still completely intact, therefore white and clearly visible. Do not forget also the partially burned pieces of paper, that is, they have become gray but on which there is still perfectly legible text. These fragments will then be burned completely.

Step 5. Finish the job by burning the remaining pieces of paper

Collect any fragments of documents that are still intact or not completely burned, then keep them in a safe place until the fire is lit again. Use protective gloves or long metal pliers to fix the remaining fragments in the center of the fire.

Step 6. Use the remaining ash

Wait for the fire to go out and for the ash to cool down to room temperature. Use a garden shovel to fill a sack with the remains of the fire; if you have a garden you can use the ash as a natural fertilizer.

If you want, you can also pour a small amount of ash into a compost container (of course only if you haven't used a chemical accelerator to start the fire).
Ash, if sprinkled around your garden plants, will discourage snails from attempting to feed on them.
Ash can also benefit adult trees in your garden if scattered around their base.

Method 3 of 4: Shred Sensitive Documents Using a Shredder

Step 1. Get access to a paper shredder

If you have chosen to eliminate your sensitive documents by reducing them to shreds, it is very important to rely on devices designed to get the best results, such as a cross-cut shredder (unlike the common straight-cut shredders). In this way you will get much smaller pieces of paper, a factor that would make any job of reconstructing the pages by the bad guys practically impossible. Choose a device that can create paper scraps that are 1 x 100mm or less in size.

Paper shredders can be purchased in all office supply stores and are divided into 7 categories, based on the level of security that the size of the cut guarantees. The "P-1" level is the one that generates paper fragments with the largest size, while the "P-7" level is the most secure, reserved for extremely sensitive documents (for example covered by state secrets). Anything lower than "P-4" (0, 4 x 38 mm) is not recommended for the destruction of sensitive documentation.
Most of the offices have shredders or turn to special services for the destruction of documentation. Ask your office manager if you can use the corporate shredder to delete your sensitive documents.

Step 2. Shred the documents

Once you have purchased or located a shredder device appropriate to your security needs, you can begin the actual shredding phase. Don't stop until all the documents have been deleted. If the amount of material to be disposed of is excessive for the capacity of the machine in use, be sure to empty the waste bin before continuing.

Be careful not to put your fingers or hand in direct contact with the mouth of the device. Hold the documents on the top side, so that there is enough distance between you and the blades of the shredder. Once the sheets of paper have been taken over by the machine, you can release them. Always remember that personal safety (in this case of your hands) comes first.
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Low security level. Traditional shredders (which use a straight cut) do not guarantee that an attacker will not be able, with time and patience, to rebuild the destroyed pages. Tearing the pages by hand is not an optimal choice, especially in the case of small documents (a few centimeters of paper are enough to trace a person's tax code or credit card number).

Step 3. Divide the pieces of paper into multiple bags

Once you have reduced your documents to small scraps of paper, dividing them into multiple garbage bags is a great additional security measure. Take a portion of each document, then throw it in separate baskets or bags. This way anyone interested in your information will no longer be able to reconstruct it.

Step 4. Get rid of the scraps on the scheduled day

If your litter is collected in your apartment building or office on Tuesdays, don't throw your documents away on Wednesdays. Your goal is to allow as little time as possible between the moment you throw out the trash and the moment it is collected by the collection service. The ideal solution would be to keep it safe until the day scheduled for collection, and then get rid of it shortly before the arrival of the person in the disposal service of your city.

Method 4 of 4: Shred Digital Documents

Step 1. Delete the documents

Locate any files on your computer's hard drive that contain sensitive data. Select them with the right mouse button, then choose the "Delete" option. The next step is to empty the system recycle bin. If there is no risk that someone will use advanced techniques for recovering deleted files, the procedure described is acceptable and easy to implement. However, recovering files deleted in this way can be very simple, as a large number of programs created for this purpose are available for free or for a fee.

If you know that other users may be trying to recover your deleted files, don't use this method.
If the sensitive information you wish to delete can be used against you, please do not use the steps described.

Step 2. Overwrite the data on your computer hard drive

All the information stored on the disk of your machine is encoded using the binary system consisting of only two numbers: 0 and 1. This is the basic language with which computers communicate. Programs that delete files by overwriting them (available online) delete the selected information by replacing it with a series of random strings of 0's and 1's. could make it impossible to trace the original data.

Most programs of this type perform multiple "overwrites" of data. For example, the standard adopted by the government of the United States of America provides for overwriting the data to be deleted 3 times.
Back up any information you want to keep using an external hard drive.
There are also programs, such as Eraser, which allow you to manually overwrite specific files.

Step 3. Demagnetize the hard drive

This procedure involves exposing the computer's storage medium to a strong magnetic field capable of destroying all the data it contains (this procedure can be applied to any technology based on magnetic fields). In theory, the hard drive exposed to a strong magnetic field loses its ability to store data and becomes unusable. Buying a device capable of generating such a magnetic field can cost several thousand euros. However, it is possible to rent it or purchase the services offered by companies operating in the IT sector, such as this one.

While data erased by overwriting can potentially be restored, degaussing a storage medium causes permanent damage, making it impossible to recover the data it contains. Make sure you back up any information you want to keep using an external hard drive or cloud service.
If you have a pacemaker, do not use a demagnetizer, as the strong magnetic field emitted could damage it.

Step 4. Physically destroy the hard drive

One of the safest ways to erase sensitive digital information is to physically destroy the media. To do this, you can use a simple hammer, drill or high temperatures. Regardless of the method you choose, the first step is to remove the hard drive from any external structure. If you have decided to use a hammer, remember to hit the disc exactly in the center, with all your strength. If you have chosen to use the drill instead, be sure to drill the drive chassis from side to side several times. If you prefer to use high temperatures (such as a blowtorch), be sure to completely melt the hard drive into each of its components.

When using a blowtorch, remember to wear suitable heat-resistant protective gloves and a mask to protect your face. It is best to work on a surface covered with earth, concrete or sand, to avoid the danger of starting a fire.
When using a hammer or drill, always wear protective gloves and a face cover to protect yourself from detaching any debris.
If you love firearms, you can also turn your hard drive into a target and have fun destroying it using your favorite firearm. Before proceeding, however, make sure you have a valid firearms license and take all necessary precautions.

Step 5. Permanently delete incriminating emails

Select all emails that contain sensitive information, then press the "Delete" or trash can button (depending on the program you use). Many online email services, such as Gmail, retain deleted files for a period of 30 days before permanently deleting them and making them unrecoverable by the user. After deleting your emails, check the "Deleted Items" or "Trash" folder to see if there is a copy of the messages that can still be recovered. If so, proceed to delete it.

Step 6. Clear the browsing history of your internet browser

You may need to prevent anyone from tracing the list of websites you visit regularly. Many internet browsers, such as Chrome, Firefox and Internet Explorer, make this option available to the user. Access the main menu of the program, locate the "History" item, then proceed to delete any unwanted element.

Advice

If you need to shred sensitive documents on a regular basis, purchasing a shredder could be a great investment. This is quite an expensive device, but it would save you a lot of time in your case.
Two people are needed to perform this procedure, but if you are alone you can use a classic barbecue. The fire will continue to burn if you have the foresight to feed it every 10-15 minutes with the addition of new paper. It will take about 15-25 minutes to burn the contents of a classic garbage bag full of paper. Use a metal utensil to move the paper as it catches fire, otherwise it may not burn completely. If any foreign object catches fire, be prepared to use the water hose to extinguish the fire or have a second person assist you. When you have finished burning all the documents, ask your helpers to wet the burnt paper scraps with plenty of water, until they have become a sticky black compound.
An alternative option is to keep all your sensitive documents in a safe place, and then burn them once a year. Alternatively, you can try to rely on the service for the destruction of documents in safety in your city; search online, it will often give you a way to shred CDs, tapes and even hard drives.