Unambiguous and irreversible cash degradation

All over the world, the number of explosive attacks on ATMs is increasing. The need for a solution is urgent. We are convinced that the gas attack Modus Operandi can only be eradicated if we remove the criminal’s motivation to rob an ATM; the availability of cash money inside an ATM. We need to degrade the cash; unambiguously and irreversibly.

Banknotes immediately lose their value, if you can’t pay with them. This means cash degradation is only effective if it’s unambiguous and irreversible. In our previous article, we wrote about the two available methods of cash degradation; the traditional and most well-known is by using ink. The latest development is by using glue. If we’re talking about unambiguous and irreversible degradation, there are quite some differences between these two methods.*


When using glue as a degradation agent, the banknotes are glued together into a solid ‘brick’. If you try to separate a banknote it will tear, obviously changing the physical properties of the banknote. The size and weight of the banknote will be changed; visibly ànd tangibly. This is why these degraded, worthless pieces of banknotes will never be accepted by a cashier, nor an automated payment center.

An ink-based degradation system sprays colored ink over the banknotes in the cash cassette. Every banknote will be partially stained with this ink. Although they should be clearly identifiable as a result from a crime, shops and automated payment centers do still regularly accept these colored banknotes. This is because ink is just a cosmetic degradation; the physical properties (size and weight) of the banknotes remain the same. Under poor lighting conditions, the degradation might not even be noticeable. Information campaigns and ink detection systems have been developed in order to prevent ink stained banknotes from being accepted.

As long as criminals can still spend (or launder) their ink covered cash, the ATM will remain an alluring target.


Ink solution suppliers claim their ink is indelible and permanent. However, the evidence of ink stained banknotes being found in circulation is abundant. Many examples exist where the ink has been washed or faded considerably leading to acceptance of the banknotes as legal tender. And central banks still find them in circulation, which proves ink is far from perfect.

Not all inks are created equal. Some manufacturers have only tested their solution on ‘specimen’ banknotes and not real banknotes. Real banknotes might be wrinkled, contaminated or otherwise compromised by daily use. This will influence the results of the degradation. When purchasing an ink solution, it’s important to know what type of ink is being used and how it has been tested.

Where glue degradation is concerned: there’s no reversing a torn banknote, once a shred has been torn from the ‘brick’. Shreds can’t be invisibly patched back together, without drastically changing the look and feel of the banknote. Size and weight will be different from the original. No examples are known where glue has been successfully removed from banknotes, nor have glued banknotes ever been found in circulation.

Choosing a cash degradation solution

If you want to deploy cash degradation inside your ATMs, choosing a method is the first step. Subsequently, you will have to choose between systems from different suppliers – which is not easy. These solutions will have some major differences. When choosing your perfect solution, you should at least consider these 7 critical success factors:

  1. Degradation of the banknotes (visible, tangible and irreversible)
  2. Health & Safety
  3. Activation mechanism (passive or active)
  4. Consequences of an activation for the ATM
  5. Certification and legislation
  6. Price
  7. Position of the degradation module in the cash cassette


Mactwin wrote a whitepaper, extensively covering these 7 considerations. ATM owners and service parties can request this whitepaper, free of charge, on our website.