How Long Will Your Fibre Last?

How Long Will Your Fibre Last?

How Long Will Your Fibre Last?


Optical Fibre is made of a particular type of glass (fused silica) which is inherently more fragile than copper internet cables. However, even though the fused silica may look and feel brittle, if used and processed correctly, these fibre cables have proved to be extremely durable.


Certain attributes are assessed when measuring the material’s durability, these being:

  • Initial strength
  • Rate of degradation
  • Any flaws that can weaken it
  • Reagents that can weaken it
  • Its optical lifetime - as the silica must still be able to function satisfactorily

With this is mind, there are essentially four factors that will affect the longevity of your fibre network:


1.    Surface flaws

Silica glass is highly resistant to degradation when its surface is free of defects, however, surface flaws can arise and reduce the material’s longevity under certain conditions. The degradation starts off slowly but can eventually lead to failure. To avoid this, fibre suppliers carry out ‘proof testing’ where they stretch the fibre to deliberately break the larger flaws.


2.    Reducing degradation

Once the flaws have been diminished, the remaining smaller degradations need to be protected by coating the fibre with a protective and durable material which will prevent new flaws from forming.


3.    Installation strains

Stress is a major factor of fibre degradation. Executing techniques of pulling, pushing and blowing are done in order to strengthen the wires and prevent further damage.

Through this process, stress applied to the cables is limited by the strength elements in the fibre. The tensile stress caused through elongation does not damage the cables but rather helps build up the cables strength and resistance to damage.


4.      Environmental factors

The local environment has a large effect on the lifespan of a fibre network. These elements, such as high temperatures, cause the cables to crack and can lead to overall failure. However, water is the largest threat to the lifespan of fibre cables as the growth of cracks under this type of stress causes “stress corrosion” which could eventually lead to general failure.


Overall, fibre is a highly durable substance which is resistant to many forms of stress. Provided that fibres are stored and coiled correctly, these connections will be able to last many years to come as original flaws begin to heal with time.