paper shredder
A document shredder , also known as a shredder , paper grinder or office shredder , is a device for shredding documents .
history
The first patent for an electrically powered document shredder was granted to the US inventor Abbot Augustus Low in 1909. However, his invention was never mass-produced. The first document shredder manufactured in large numbers was built in Balingen in 1935 . Originally it was driven with a hand crank, later with an electric motor. The company founded by Adolf Ehinger still exists today. Until the early 1980s, document shredders were rarely used by private individuals.
functionality
Before the introduction of electrically operated paper shredders on the market, thermal paper shredders ( fire cages ) were in widespread use. Because of the risks involved in dealing with open fire and not least because of the dirt that is created, electromechanical shredders of various designs have become established today.
A document shredder cuts the document into such small parts that they contain hardly any usable information on their own and could only be put back together correctly with great effort.
Simpler document shredders only cut the paper into narrow strips (strip cut). Better paper shredders cut additional horizontal cuts. This cutting method is known as particle cut, whereby the term cross -cut is also common.
Newer document shredders can also shred credit cards and CDs or DVDs in addition to paper . For some years now, document shredders have also been used increasingly in private environments.
Cutting units
In the case of document shredders, a distinction is essentially made between strip cuts and particle cuts .
When cutting strips , the cutting mechanism consists of two opposing shafts that are equipped with a certain number of offset, interlocking, sharp-edged wheels. In addition, the casing of the individual wheels is toothed, which ensures that the clippings can be transported properly. The actual cutting process consists in the fact that the cut material passes the interlocking wheels and is thereby divided into strips, the width of which corresponds to the distance between the wheels. The length of a strip corresponds to that of the inserted document. As a result, the greater the number of wheels on the shaft, the greater the number of strips with the smaller the width. The main advantage of the strip cut is that the capacity of several sheets to be processed at the same time is regularly higher than with particle cut. In addition, the operating noise is significantly lower. However, the volume of the clippings is much higher and no particularly high security levels can be achieved.
The cutting mechanism in the particle cut also consists of two opposing shafts with a certain number of offset, interlocking, sharp-edged wheels and the lengthwise division of the written material is thus done in the same way as with the strip cut. However, each wheel is designed in such a way that a sharp metal edge protrudes from the jacket, which ensures both the transport of the cut material and the division of the strip into several particles. So that this process takes place in a balanced way, the metal edges of the wheels are mounted slightly offset, almost in a wave shape. The advantage of the particle cut lies essentially in the higher security level that can be achieved. In addition, the volume of the clippings is much smaller. The considerably louder operating noise can be viewed as a disadvantage.
drive
Most devices are driven by an electric motor that drives the gearbox, which is usually attached to the side of the cutting unit and consists of several gear wheels, via a spindle shaft. However, there are a few devices that are driven by a hand crank instead of an electric motor.
The actual performance of the device depends on the nature and dimensions of the gear unit and the materials used for it. Devices with particularly high performance therefore usually have a chain drive , while devices in the lower performance range are content with gear wheels , some of which can be made of plastic.
Importance of the shredder
Cutting paper into small pieces has the advantage that it is safer and easier to carry out in everyday office life than other methods of shredding files (e.g. burning) and that the paper scraps can also be recycled. With a very fine cross cut, however, the paper fibers are so short that only inferior types of paper can be made from them.
Standardized shredding stages (new standard DIN 66399-2 from 2012)
With the introduction of the General Data Protection Regulation , DIN 66399 will be used in Germany for the security levels when shredding files. Compared to the previous definition (see also DIN 32757), this is based on different cut formats. Different materials are divided into classes, for paper the security levels start with "P":
- P-1 allows a maximum area for shredding of 2,000 mm² or a strip of any length with a maximum width of 12 mm. Up to 10% of the material may even have an area of up to 3,800 mm². An A4 sheet of paper torn into 32 parts fulfills this requirement. This corresponds to a snippet size of approx. 52 × 37 mm, a little less than half a business card.
- P-2 reduces the area to 800 mm² or strips of any length with a maximum width of 6 mm. Up to 10% of the snippets may have the standard size of P-1 (2,000 mm²). To meet the requirement, a DIN A4 sheet of paper must be torn into 78 equal parts.
- P-3 reduces the permitted snippet size to a maximum of 320 mm² or strips of any length with a maximum width of 2 mm. Here, too, there is a tolerance of 10% of the snippets up to the previous level (800 mm²). A DIN A4 sheet has to be divided into 195 equal parts for this.
- P-4 no longer allows stripes to be cut. 10% of the snippets may be up to 480 mm² in size, but a maximum of 160 mm² per particle is required. In addition, each particle may not be more than 6 mm wide on one side. For a DIN A4 sheet, this requires shredding into at least 420 pieces. A common particle size for document shredders is 4 × 35 mm, with which the security level is well maintained.
- P-5 reduces the maximum width to 2 mm and the area per particle to 30 mm². At this stage 10% of the particles can be up to 90 mm² in size. To meet this security level, a DIN A4 sheet of paper must produce 2,100 particles without tolerance. Document shredders of this security level often produce standard particles of 2 × 10 mm in size, so that a folded sheet also remains within the permissible tolerance when cross-cut.
- P-6 allows the size of P-5 (30 mm²) for 10% of the particles, otherwise it requires a maximum of 10 mm² with a maximum width of 1 mm. This breaks a DIN A4 sheet of paper into a puzzle of 6,300 particles, each of which may not be more than 1 × 10 mm in size.
- P-7 does not allow any tolerances for the maximum permissible particle size of 5 mm², which may not be more than 1 mm wide. A DIN A4 sheet of paper turns into at least 12,600 really small particles, each 1 × 5 mm.
Different dimensions apply to other material categories:
-
Category F concerns reductions, typically movies
- F-1 max. Particle size 160 mm²
- F-2 max. Particle size 30 mm²
- F-3 max. Particle size 10 mm²
- F-4 max. Particle size 2.5 mm²
- F-5 max. Particle size 1.0 mm²
- F-6 max. Particle size 0.5 mm²
- F-7 max. Particle size 0.2 mm²
-
Category O applies to optical data carriers (e.g. CD, DVD, BluRay)
- O-1 max. Particle size 2,000 mm²
- O-2 max. Particle size 800 mm²
- O-3 max. Particle size 160 mm²
- O-4 max. Particle size 30 mm²
- O-5 max. Particle size 10 mm²
- O-6 max. Particle size 0.5 mm²
- O-7 max. Particle size 0.2 mm²
-
Category T applies to magnetic data carriers (floppy disks, ID cards, cassettes, tapes)
- Make T-1 inoperable (e.g. crumple, cut)
- T-2 max. Particle size 2,000 mm²
- T-3 max. Particle size 320 mm²
- T-4 max. Particle size 160 mm²
- T-5 max. Particle size 30 mm²
- T-6 max. Particle size 10 mm²
- T-7 max. Particle size 2.5 mm²
-
Category H refers to magnetic data carriers with higher data density (hard disks)
- Make H-1 inoperable (e.g. bend parts)
- Damage H-2 (e.g. tear off plug connection)
- Deform H-3 (e.g. break magnet carrier)
- H-4 max. Particle size 2,000 mm²
- H-5 max. Particle size 320 mm²
- H-6 max. Particle size 10 mm²
- H-7 max. Particle size 5 mm²
-
Category E finally describes electronic data carriers (USB sticks, mobile phones)
- Make the E-1 inoperable (e.g. damage connections)
- E-2 part
- E-3 max. Particle size 160 mm²
- E-4 max. Particle size 30 mm²
- E-5 max. Particle size 10 mm²
- E-6 max. Particle size 1.0 mm²
- E-7 max. Particle size 0.5 mm²
For general use, the security levels are divided into three classes:
- Class 1 is intended for documents that can be damaged by publication or misuse of the data. This includes security levels 1–3.
- Class 2 is to be used for confidential data, such as medical files. It covers security levels 4–5.
- Class 3 is used for the destruction of strictly confidential or secret data. Security levels 6–7 apply for this.
Standardized shredding stages (old standard DIN 32757 to 2012)
|
DIN 32757 |
|---|---|
| Area | Office and data technology |
| title | Destruction of information carriers - Part 1: Requirements and tests on machines and equipment (withdrawn), Part 2: Machines and equipment; Minimum information |
| Brief description: | Data security of a document shredder |
| Latest edition | 1995-01 / 1985-10 |
| ISO | - |
|
|
DIN 66399 |
|---|---|
| Area | Office and data technology |
| title | Office and data technology - Destruction of data carriers - Part 1: Basics and terms, Part 2: Requirements for machines for the destruction of data carriers |
| Latest edition | 2012-10 |
| ISO | - |
|
|
DIN EN 15713 |
|---|---|
| Area | Office and data technology |
| title | Secure destruction of confidential documents - procedural rules |
| Latest edition | 2009-08 |
| ISO | - |
In Germany, the data security of a document shredder is assessed according to the five security levels of the DIN standard DIN 32757. The highest security level 5 was hardly used in practice, security level 2 or 3 was the most common. A few manufacturers also advertised security level 6, which is not standardized in DIN 32757.
In detail, the six security levels for paper are defined as follows (DIN 32757-1: 1995-01):
-
Security level 1 (recommended for general written material)
- with strip cut: max. 12 mm strip width
- with cross cut: max. 1000 mm² particle area
-
Security level 2 (recommended for internal, not particularly confidential documents)
- with strip cut: max. 6 mm strip width
- with cross cut: max. 400 mm² particle area
-
Security level 3 (recommended for confidential documents)
- with strip cut: max. 2 mm strip width
- with cross cut: max. 4 mm width to max. 60 mm particle length (240 mm² particle surface)
- but for plastics (such as identification cards or microfilm): max. 1 mm² particle area
-
Security level 4 (recommended for confidential documents)
- Cross cut: max. 2 mm width to max. 15 mm particle length (30 mm² particle area)
- but for plastics (such as identification cards or microfilm): max. 0.5 mm² particle area
-
Security level 5 (for maximum security requirements)
- Cross cut: max. 0.8 mm width to max. 15 mm particle length (12 mm² particle area)
- crushed coarse ash, suspension, solution or fibers
- but for plastics (such as identification cards or microfilm): max. 0.2 mm² particle area
-
Security level 6 (for secret service security requirements)
- Cross cut: max. 1.0 mm width to max. 5.0 mm particle length (5 mm² particle area)
- crushed fine ash, suspension, solution or fibers
The following should be noted about the security levels according to DIN 32757:
- Due to the double definition of the cross cut, it is possible that a document shredder has a higher security level for A4 sheets than for continuous paper.
- For plastics such as identification cards or microfilm, smaller material particle areas apply than for paper.
DIN 32757-1 was withdrawn in October 2012 and replaced by DIN 66399-1 + 2. Compared to DIN 32757-1: 1995-01, the series of standards has been restructured, the basics and terms have been included in Part 1, requirements for machines and testing are defined in Part 2; In addition, the new security levels 6 and 7 have been introduced. The requirements for the operating instructions are now included in Part 2.
A European standard has been published since August 2009 . This is EN 15713: 2009, which is valid in Germany as DIN EN 15713. A new table is listed in Appendix 1A which regulates the new document destruction levels. The previously misleading term of the security level has been replaced across the EU by the term "shredding level".
| Categories of confidential documents according to DIN EN 15713: 2009-08 | |
|---|---|
| category | description |
| A. | Paper, plans, documents and drawings |
| B. | SIM cards and negatives |
| C. | Video / audio tapes, floppy disks, cassettes and films |
| D. | Computer including hard drive, embedded software, chip card reader,
Components and other hardware |
| E. | ID cards, CDs and DVDs |
| F. | Counterfeit goods, printing plates, microfiche, credit and loyalty cards and others
Products |
| G | Company or branded clothing and uniforms |
| H | Medical X-ray and overhead projector panels |
|
Note: Hazardous waste is not included in this table. The users are aware of the presence
of applicable laws on the destruction and / or disposal of hazardous waste. |
|
| Material-specific shredder and fiberization sizes according to DIN EN 15713: 2009-08 - Appendix 1A | |||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|
| Crushing
No |
Medium
surface of Materials (in mm²) |
Maximum
Cutting width (in mm) |
Procedure of
destruction |
Material categories
+ acceptable - unsuitable for the material |
|||||||
| A. | B. | C. | D a | E. | F b | G b | H | ||||
| 1 | 5000 | 25th | Shredding | + | - | + | + | - | / | / | + |
| 2 | 3600 | 60 | Shredding | + | - | + | + | - | + | ||
| 3 | 2800 | 16 | Shredding | + | - | + | + | - | + | ||
| 4th | 2000 | 12 | Shredding | + | - | + | + | - | + | ||
| 5 | 800 | 6th | Shredding or
Unravel |
+ | - | n / A | + | + | n / A | ||
| 6th | 320 | 4th | Shredding or
Unravel |
+ | - | n / A | + | + | n / A | ||
| 7th | 30th | 2 | Unravel | n / A | + | n / A | + | + | n / A | ||
| 8th | 10 | 0.8 | Unravel | n / A | + | n / A | + | + | n / A | ||
|
a Category D documents should be destroyed in such a way that the information carrier is illegible and safely disposed of.
b Client and material specific. |
|||||||||||
Differences in the paper shredders
In addition to the security level according to the various security standards, the main differences are in particular the sheet feed width, auto start and especially auto stop. The mechanical autostart is activated by a small lever located in the immediate vicinity of the cutting unit, which is moved from its basic position by the material being cut. Thus, the cutting unit runs at least as long as the introduced clippings hold the lever in the appropriate position. The mechanical auto stop includes the overrun, which guarantees that the document actually passes the cutting unit in its entirety. When the lever has returned to its home position, a roller belonging to the same construction engages in the thread of a shaft of the gearbox. When the shaft rotates, the roller is transported outwards and when it falls it triggers the cutting unit to switch off. Modern devices have a light barrier control that triggers the cutting unit and electronically controls the overrun. The autostart or autostop function also ensures greater acceptance of the devices because simply inserting the information carrier into the device immediately triggers its destruction. A separately required switch-on or switch-off process is often found to be cumbersome and as a result a number of documents are initially collected before the device is used. This creates a security risk. Common document shredders often have both automatic activation and a mode for permanent "On" and for "Off".
A technical implementation of an "AutoFeed" option enables a complete stack of paper to be inserted, so that manual insertion of individual sheets is not necessary.
Dangers for the user
Most devices are designed to be safe and therefore prevent accidents. Contact switches, for example, ensure that the devices only work when they are on the corresponding container or the device door is locked. This reliably prevents direct contact with the cutting unit on the underside of the device. In principle, it is difficult to avoid a risk to the user that is caused by the feed slot for the material to be destroyed. This is reinforced by the fact that more powerful devices usually also have a larger feed slot. Therefore the user should
- work concentrated on the machine and not be distracted,
- Exercise particular caution with long, loose hair,
- Take off jewelry, such as long necklaces and bracelets, before using the device
- Also exercise caution with loose items of clothing, especially scarves, scarves and ties.
The mentioned items of clothing and jewelry can be caught by the cutting unit together with the material to be processed if carelessly.
Document shredders that are good for everyday use can also handle overlooked staples or paper clips. These cannot damage the device.
Most common document shredders are not designed for continuous operation. Some, mostly smaller, devices therefore have a heat protection switch, which automatically guarantees the shredder 15 to 30 minutes of cooling after one to two minutes of continuous power.
Shredding
There are rules according to which certain files must be destroyed after a certain period of time. An example:
In the Codex Iuris Canonici (the code of law of the Catholic Church), Canon is 489
§1: “In the diocesan curia there must also be a secret archive, but at least a separate cupboard or a separate compartment in the general archive, which is tightly locked and secured so that it cannot be removed from the location; The documents to be kept secret must be kept in it with the greatest care. "
§2: "Annually, the files of criminal cases in moral proceedings whose defendants have died or which have been convicted for a decade must be destroyed; a short fact sheet with the wording of the final judgment is to be kept. "
This regulation led and leads to the fact that older cases of sexual abuse in the Roman Catholic Church cannot be dealt with in detail.
Conversely, there are a number of legal regulations that provide for the storage of files for a certain minimum period. Furthermore, management systems (example: ISO 9001: 2015) often contain archiving deadlines set internally in the organization or in the company. The archived documents may only be destroyed after this retention period has expired .
Individual evidence
- ^ Waste-paper receptacle
- ↑ Historical overview of the development of the document shredder
- ↑ Technical Committee CEN / TC 263 "Secure storage of money, valuables and data carriers" (Secretariat: BSI; United Kingdom) of the European Committee for Standardization (CEN): DIN EN 15713: 2009-08 - Secure destruction of confidential documents - Rules of procedure . In: DIN EN 15713 . Beuth Verlag GmbH, Management Center: Avenue Marnix 17, Brussels 2009, p. 8 .
- ↑ a b c Abuse in the Catholic Church: In the Secret - Inland - FAZ .
