Most of us are used to haggling with vendors or taxiwalas because the notes that they are giving us consist of unfit notes. Some are soiled, others torn and some even, taped to perfection. And then by chance, if we manage to have a small collection of disfigured notes, we approach the local vendor who exchanges 'phate purane note' for a fee. But the simpler way to do it is by approaching the nearest bank. Banks, on their part, have specific definitions for different physical states of currency notes and they handle them, according to their condition. While individuals might not find the technical details important, but knowing the classification may help in some situations.
UNFIT
These are notes that cannot be recycled back by banks into the system because of their poor physical condition. The Reserve Bank of India also withdraws some series of notes as they are deemed unfit. In the latter case, even if the note is in good physical condition, it is unusable.
Currency notes are regularly sorted by the banks to check for their genuineness and fitness.
GETTING DIRTY
A common term 'a soiled note' is used when dirt accumulates on the note. This can also occur as the note ages over time and becomes yellow or even decolourises due to excessive usage. As a result, it may lead to loss of reflectivity that can be witnessed on either side of the note. When such conditions are prominent (considering maximum density difference, minimum reflectance and filters), then it will be called unfit and withdrawn from circulation.
Another reason for the note to become unfit would be stains on the currency. Notes can get stains due to accidents and even due to the manner and place where they are kept. These are, obviously, not part of the original note design.
Banks have criterias based on dimensions of stains to classify them as unfit. There are other situations when people write on them. These alterations are known as graffiti. In such cases, bank again checks the dimensions of the stains to classify it as unfit. Sometimes, even the ink can can go missing.
PHYSICAL PARAMETERS
The other thing that happens with currency notes is limpness. This is asituation where there is deterioration leading to lack of stiffness due to excessive usage or mutilation. However, banks don't withdraw these notes just because of lack of stiffness. There have to be other disparaging factors like damage before they are taken out of circulation. For instance, a torn note is classified as unfit if it has vertical tears of 8 mm, horizontal tears of 15 mm and diagonal tears of 18 mm in length and 4 mm in width. If the note has any such tears, it is taken out of circulation.
A lot of people also have the habit of folding the notes. And over a long period of time if such folds result in a reduction of the length or width by more than 5 mm, the note becomes unfit.
BREAKUP AND REPAIRS
If the note is torn and has more than two pieces, it will be taken out of circulation. When a complete portion is missing, it becomes an imperfect note. Such notes include those that are partially or fully shrunk or washed or even altered. There can also be a mismatched note, which is formed by joining two halves of different notes. All of these would be classified as being unfit for circulation.
There are a lot of cases whereby the note is repaired, using some external material. This could be various types of tape or paper or even glue. Just because a note is repaired does not make it unfit for use. However, specific dimensions determine this categorisation. If the repairs cover an area more than 100 sq mm, then this would be unfit. Similarly, if the material used for repair is thicker than a specified dimension or the length or width is more than 10 mm, then this would be classified as unfit. Keep an eye on all these factors while handling currency notes.
