Comparison ShredMARK 1830M vs ShredMARK 715M

The level of secrecy of the shredder according to the DIN 66399 standard. It is designated by the English letter P (from “paper”) and a number from 1 to 7.

This indicator determines how well the destruction is carried out, as well as how difficult it will be to restore the document or medium passed through the device. The DIN 66399 standard provides for seven security levels with the simplest numbering from the lowest to the highest: P-1, P-2, P-3, P-4, P-5, P-6, P-7. These levels apply to both paper and other media, but shredders are used primarily for paper documents, and this option will be discussed here; similar information about other materials can be found in the "Destroys" section.

— P-1. The paper is cut into strips no more than 12 mm wide or into fragments up to 2000 mm² in area. Basic level, allowing for the easy restoration of a destroyed document; designed for the disposal of papers that do not contain classified information.

— P-2. The paper is cut into strips no more than 6 mm wide or into fragments up to 800 mm² in area. From a practical point of view, it has no fundamental differences from level P-1 — except that the shredder basket does not fill up as quickly due to the smaller size of the...fragments.

— P-3. The paper is cut into strips no more than 2 mm wide or into fragments up to 320 mm² in area. It is impossible to restore a document destroyed in this way manually, although this can be done using special technical means.

— P-4. The paper is cut into fragments no more than 6 mm wide and no more than 160 mm² in area. This level is considered to be almost the most optimal for “delicate” materials that at the same time do not require maximum levels of secrecy — for example, everyday business documents like financial statements. Restoration after processing at level P-4 is extremely difficult even with the use of special equipment (although possible), while the shredders themselves are relatively simple and inexpensive. In addition, they can easily be designed to destroy paper clips and staples.

— P-5. The paper is cut into fragments no more than 2 mm wide and no more than 30 mm² in area. This level is suitable for business documents of strategic importance, such as long-term plans.

— P-6. The paper is cut into fragments no more than 1 mm wide and no more than 10 mm² in area. After such processing, document restoration becomes virtually impossible.

— P-7. Maximum level of secrecy: paper is cut into fragments no more than 1 mm wide and no more than 5 mm² in area. Such shredders are very expensive, and they are not very productive. Therefore, it makes sense to use them for documents of special state importance and other materials of similar significance.

It is also worth noting that when working with paper, the level of secrecy affects the speed of filling the shredder basket. The smaller the paper fragments, the more densely they fit into the basket and the more time it takes to fill it, with the same volume.

Types of media and materials that the shredder can utilize. Note that, by definition, all such devices are capable of working with paper documents, so paper is not mentioned in this paragraph (some models are generally only compatible with paper and do not allow using other materials). However, shredders with the ability to utilize various additional items are more common — mainly staplers, paper clips, credit cards and/or CDs/DVDs. Here are the features of each of these options:

— Staples. An auxiliary function designed to ensure that stapled materials do not have to be separated before being loaded into the shredder. Allows you to significantly save time when utilizing of such materials, especially in large volumes; also provides a correct operation guarantee in case of accidental contact with the staples.

— Paper clips. Paper clips are removed much easier than staplers and there is no problem with them even with a large amount of documents. Therefore, this function is rather an insurance against getting such a clip into the device along with the document.

— Credit cards. The ability to recycle various plastic cards with magnetic media — credit cards, passes, etc. This feature at least prevents the illegal use of such cards, and with a high security level it allows you to...keep the fact of the existence of a card in secret. Actually, the security level for such utilization is indicated in the generally accepted standard DIN 66399, as like as for paper, and there are seven of them:

• 1 — the card remains intact, its surface is mechanically damaged;
• 2 — the card is cut into pieces with an area of less than 2000 mm²;
• 3 — size of pieces less than 320 mm²;
• 4 — less than 160 mm²;
• 5 — less than 30 mm²;
• 6 — less than 10 mm²;
• 7 — less than 2.5 mm².

— CDs/DVDs. Ability to utilize optical discs, which can also store confidential information. For such media, DIN 66399 also provides 7 security levels:

• 1 — the disk is cut into pieces with an area of less than 2000 mm²;
• 2 — less than 800 mm²;
• 3 — less than 160 mm²
• 4 — less than 30 mm²;
• 5 — less than 10 mm²;
• 6 — less than 5 mm²;
• 7 — less than 0.2 mm².

The largest possible size of the fragments that come out from the shredder after being processed. However, it's told about fragments only in the case of using cross-cutting; for stripe cut models (see “Cut Style”), this item indicates the largest width of the stripes. The size of the fragments is directly related to the security level provided by the shredder; see the relevant paragraph above for details.

The number of sheets that the shredder is capable of processing at one time — in other words, the largest size of a stack of sheets that can be loaded into the device. Most modern shredders can handle multiple sheets; up to 5 pcs at a time is considered a very limited indicator, up to 10 pcs — a small one, 11 – 15 pcs can be called an average value, 16 – 20 pcs — quite good, and in the most powerful models this figure exceeds 20 pcs.

Note that this parameter is given for paper of a certain grammage (and, accordingly, thickness). At the same time, the East European standard for office paper is a grammage of 80 g/m², and in many European countries thinner paper is used with a grammage of 70 g/m², and it is for it that the capacity of many shredders is indicated. Therefore, if this moment is not specified in the specs, it is best to load the shredder not up to limit values, making a margin of 1 sheet per 8 sheets of capacity — 1 sheet with a stack thickness of up to 8 sheets, 2 sheets with a stack thickness of 8 to 16 sheets, etc. However, other conditions for density may be specified in the user manual.

Also note that the number of sheets per load is determined by manufacturers based on the results of tests under perfect conditions — in the absence of staples on paper, with low humidity,...optimal voltage in the mains, perfect sharpening of knives, etc. In fact, any deviation from these indicators affect some decrease in efficiency.

The duty cycle of the shredder is the maximum time that it can work without interruption.

Limit of operating time is due to the fact that the destruction of documents and other media is associated with quite significant loads on the electric motor and gear. This leads to strong heating, while the breaks allow the hardware of the shredder to cool down. Actually, there are models with the possibility of continuous operation, but they are expensive and not always really necessary; see "Features" for details.

In small shredders for domestic use, the work cycle is often only a few minutes, and among powerful professional devices there are values of half an hour or more. Also note that in some models, shutdown after a full cycle is provided automatically due to overheating protection (see "Features"), however, the presence of such a system does not mean the presence of an automatic shutdown on time — it can only work with a critical increase of temperature.

The minimum break time required by the shredder after a full cycle of work (see above).

A break is required so that the motor and mechanisms of the device can cool down after the intense loads that they are subjected to during operation. Moreover, if the operating time was less than a full cycle, then the break can also be made shorter; however, if the device has worked for more than half of the cycle, for a full assurance it is still worth to take a break for all the time intended for it. Some models may provide other recommendations in this regard — they should be specified in user's manual.

The volume of the waste bin that is filling with shredded materials after passing through the shredder. The larger it is, the less often you will have to empty the basket; at the same time, large containers increase both the weight and dimensions and the cost rate of the device. For comparison: the volume of a standard household bucket is about 10 liters, a shredder with a basket of such a capacity will have dimensions of about 35x30x15 cm and belongs to the entry level in terms of capacity.

— Auto start/stop. The system of automatic switching on and off of the shredder facilitates its use. To control the process in such models, you do not need to press buttons or perform any other additional actions: just place the processed material into the working gap and the shredder will start the utilizing process itself, and turn off automatically upon completion.

— Reverse. Possibility of rotation of knives of the shredder in reverse direction. This feature has several uses. One of the most obvious is to correct the situation when the knives are jammed (for example, if a stack of paper is too thick) or the mechanisms are clogged: by turning on the reverse, you can easily remove jammed materials from the working mechanism. Also, the reverse can be useful in cases where it was necessary to clarify something from an incompletely cut document. In addition, the disposal of plastic cards and optical discs (see “Destroys”) in most cases (although not necessarily) is carried out precisely in the reverse mode.

— Continuous work. This feature means that the shredder does not require interruptions in work and can utilize of a large amount of documents without any pauses (at least regarding daily duty cycle — see above). Such units are extremely convenient for large volumes of work, when the volume of a single portion of recyclable materials can be measured in thousands of sheets. On the othe...r hand, continuous operation requires very high reliability of the motor and gear, which significantly increases the cost. So it makes sense to specifically look for a model with the possibility of continuous operation only in cases where this function is fundamentally important.

— Overheat protection. A security system that automatically turns off the shredder's motor when its temperature increase to critical level (usually this happens during long work at high loads). This allows you to avoid unpleasant consequences — from the breakdown of the device to the open fire. Note that in some models, overheat protection plays the role of a circuit breaker that trips at the end of the work cycle (see above); in others, this function only works in abnormal situations, with a significant increase in temperature due to a serious malfunction.

— Bin full autostop. A sensor that monitors the fullness state of the basket and automatically turns off the device when it is full. Such a function not only eliminates the need to constantly monitor the fullness of the basket, but also prevents overloading due to the inability to push the next pack of materials into an overflowing waste bin.

The maximum noise level produced by the shredder during operation. The lower this indicator, the quieter the device works and the more comfortable it is to use, the better it is suitable for conditions that require silence (for example, libraries or archives).

When assessing the noise level, it should be taken into account that the decibel is a non-linear measure unit, and noises with a difference of several decibels differ in volume by several times. For comparison, we can proceed from the following data: office shredders, positioned by the manufacturer as "quiet", have a noise level of about 55 – 60 dB, which corresponds to the volume of ordinary human speech. 65 dB can be compared with a loud conversation, 70 – with a noisy street, 75 – with a scream, and there is practically no higher volume among office models.