The Functionality of Paper Shredders

Picture a powerful U.S. National Security Council staffer, with an air of military authority. While Justice Department officials, just around the corner, are hunting for clues on the most significant political scandal in Washington, the staffer turns to his secretary, the glamorous Fawn Hall (whose name could've come straight from an Ian Fleming novel), to help him obliterate evidence linking him to the controversy.

This isn’t a spy thriller – the protagonist isn’t a smooth-talking charmer, but rather a bulky figure overwhelmed by pressure. The paper shredder isn't the type to order a martini, shaken or stirred.

However, it was the paper shredder that captured the public's attention during the 1987 Iran-Contra hearings, when Lt. Col. Oliver North testified about the 46-centimeter stack of memos he and his secretary Fawn Hall desperately fed into its iron jaws [source: Benac].

This brings us to the often misunderstood image shredders have in the media. Like an unruly pet blamed for its owner's poor training, the paper shredder is frequently seen as a symbol of corruption, greed, and other misdeeds. However, the machine is capable of good, and in the best cases, it can thwart criminals: no identity thief obsessed with paper will be able to snatch your PIN or bank details if a shredder is in the picture.

Governments don't only employ shredders for nefarious purposes; shredding is such an essential part of government operations that the U.S. National Security Agency even evaluates paper shredders to ensure they meet the required standard for particle size – no larger than 1 millimeter by 5 millimeters [source: SEM]. A small shredder that meets these NSA standards may cost a few hundred dollars. But for a Kobra Cyclone that shreds 500 sheets at once with varying particle sizes, you’re looking at a price range of $20,000 to $30,000 [source: Mono Machines].

A bit expensive for a machine that simply tears things apart? Let's rewind to a time when shredders were far more basic.

Abbot, Adolf and Information Destruction

While it’s unclear exactly when shredders became necessary for eliminating crucial secrets, we know that in 1909, Abbot Augustus Low filed the first U.S. patent for a shredder-like 'waste-paper receptacle.' He described its purpose as 'for disposing of waste paper and is designed more particularly for use in offices and other places where not only the collection and storage of waste paper is desirable, but also its cancellation or mutilation in such manner as to render it unavailable or unintelligible for re-use or for information' [source: Low].

Low’s invention used a cutting or grinding mechanism that ensured paper would be shredded into small pieces before it hit the bin. It could be operated either by an electric motor or a manual crank. He also included an automatic stop feature for the motor: two electric switches created a circuit when paper was fed in, allowing the motor to run. When the paper ran out, the second switch would break the circuit and stop the device.

So, did everyone rush to use paper shredders in 1909? Not at all. Despite the brilliance of Double-A Low (not his real nickname), the device wasn’t marketed to a wide audience, and the budding paper-shredding industry quietly bided its time, preparing to eventually dominate every accountant’s office.

In 1935, German toolmaker Adolf Ehinger filed for a German patent for his version of the paper shredder. Unlike Low, Ehinger was a savvy businessman. Post-World War II, he found a lucrative niche, marketing shredders to the usual players: government, military, and financial institutions.

Can you guess which major global event, filled with spy films, high-level conspiracy, and shady dealings, turned the paper shredder into an essential tool for government operatives? Yes, it was the Cold War of the 1950s. The devices were aggressively marketed during this time. After all, what’s a gripping spy novel climax without papers being shredded just as the Russians are breaking down the door?

We’ll return to explore how the shredder became a fixture in modern pop culture and history, but first, let’s take a closer look at how shredders actually work. (And then destroy all the evidence of this inquiry.)

Shredders: Sinking Their Teeth Into Your Personal Info

It seems pretty straightforward: you feed paper into the shredder, and its little teeth munch away at it. Once the paper is fully shredded, the machine stops. Easy, right?

However, once you dive into the mechanics, things get a little more complicated. How does the shredder know when paper has been inserted? How does it detect when the paper is done? And, if given the chance, would it treat -- say -- my hair the same way?

Let’s begin with the basics and focus on the smaller shredders we commonly see in offices. These devices typically slice paper into either strips or small, confetti-like squares. The shredder itself consists of a bin where the shredded paper collects. At the top of the bin is a slot where paper is fed in. Strip-cut shredders often use rotating blades to slice the paper, while cross-cut shredders employ two sets of opposing teeth to produce smaller, square-shaped particles [source: Dahle Shredder]. When paper (or another object) touches the cutting head, a sensor triggers the rotation of the sharp blades or teeth, pulling the paper into the machine and shredding it into tiny bits in the bin. There are additional sensors on the bottom of the lid; when the machine sits on top of the bin, these sensors activate the ones that rotate the cutting mechanism.

In other words, the head of the machine must be properly positioned for it to function correctly. This is a safety feature to prevent the shredder from becoming a land-based version of "Jaws" before it’s securely in place. Additionally, many shredders come with an emergency shutoff switch to quickly stop the blades if necessary.

Large industrial shredders operate in a similar manner, but instead of feeding in paper one sheet at a time, they typically have a large hopper where you can dump documents. These machines are much larger, allowing them to grab bigger items with their teeth and pull them through. It’s just like the smaller paper shredders, but on a larger scale.

And the scale can get enormous. Think about all the reasons we need shredders beyond just for paper: Ever wondered how garbage is compacted into neat bales to fit on cargo ships or in landfills? It’s shredded first. How about breaking down plastic for recycling? Shred it first. Even wood chips for playgrounds are shredded before use.

Shredders in Pop Culture

Arguably the most recognizable shredder in popular culture is the villain Shredder from 'Teenage Mutant Ninja Turtles.' However, focusing solely on machines, let's examine the role of document shredders in history and how they have appeared in the media.

What better place to begin than with Watergate? It was here that G. Gordon Liddy likely had unkind memories of 'shredding stuff left and right' using a Shredmaster 400 model [sources: Benac, Woestendiek]. Liddy would later serve over four years in prison for his involvement in concealing – or rather shredding – evidence related to the 1972 break-in at the Democratic National Committee headquarters.

As mentioned earlier, during the Iran-Contra hearings, Oliver North revealed that he used a shredder just outside the door where Department of Justice officials were reviewing his papers. In a scenario familiar to most shredder users, his machine even jammed. (Perhaps North should have invested in an upgrade; his $7,500 Intimus could shred a single sheet into 10,000 pieces of confetti in no time, but it could only process 12 sheets at once [source: Dean and Krier].

The 1979 Iranian hostage crisis also featured a shredder. The Americans had shredded a batch of documents, which the Iranians managed to reconstruct using – get this – experts in Persian carpet-weaving. (The documents had been shredded into the traditional vertical strips.) Afterward, the U.S. government mandated strict guidelines for the size of shred particles [source: Woestendiek].

After the collapse of Enron in 2002, paper shredders made headlines once again when both Enron and Arthur Andersen (the firm that audited Enron) were accused of destroying internal documents. Andersen's conviction for obstruction of justice was later overturned by the U.S. Supreme Court, which determined that the jury instructions for the conviction were too vague.

One eagerly anticipates which scandalous or dubious action will once again thrust paper shredders into the limelight. Will it be a corrupt politician? A cunning CEO? A charming yet treacherous spy trying to erase evidence of their double-agent identity? Only time will tell. But to dive deeper into the world of paper shredders, brace yourself to enter the machine that is the next page.