In the world of construction and infrastructure maintenance, one of the most challenging tasks for utility locators is identifying and mapping non-conductive utilities, particularly fibre optic cables. These cables are integral to our telecommunications infrastructure, yet their non-metallic nature makes them virtually invisible to conventional detection methods. This blog post discusses the difficulties associated with locating fibre optic cables and explores various technological solutions and best practices that can help overcome these challenges.
The Invisibility Issue
Fibre optic cables are made from glass, which does not conduct electricity, making them undetectable by standard electromagnetic equipment that locates utilities based on their metal content. This poses a significant challenge during excavation works, as unintentionally striking a fibre optic cable can lead to severe consequences, including costly service interruptions and expensive repairs. The need for precision in locating these cables is not just a matter of efficiency but also of economic importance, given the high costs associated with fibre optic cable damage.
Overcoming the Challenges with Technology
1. Ground Penetrating Radar (GPR)
GPR is a powerful technology that can detect changes in the subsurface material composition. When used by skilled operators, GPR can help identify the presence of fibre optic cables. This method sends a radar signal into the ground and reads the reflected signals to map underground utilities. GPR is particularly useful in complex environments where multiple utility lines may cross paths.
2. Careful Study of Plans
Before any excavation begins, it is crucial to review utility plans provided by services such as Dial Before You Dig (DBYD). These plans can offer preliminary insights into the possible locations of fibre optic cables. However, given that documentation might be outdated or inaccurate, relying solely on plans is insufficient.
3. Copper Trace-Rodding
To enhance the detectability of fibre optic cables, copper trace-rodding can be employed. This technique involves inserting a copper wire within the ducts that house the fibre optics and using electromagnetic equipment to locate the copper tracer. This method significantly increases the likelihood of detecting non-conductive utilities.
4. Using a Sonde for Accurate Measurements
A sonde, a specialised transmitter, can be attached to the rod used in trace-rodding. It emits a signal from a specific location, allowing for precise depth and directional measurements. This technology is invaluable for utility locators when mapping the exact positions of underground assets.
5. Potholing Optical Fibre Utilities
One of the most reliable methods to confirm the presence and exact location of fibre optic cables is potholing. This process involves creating a small test hole at the expected utility location to visually confirm its presence. Although time-consuming, it provides a direct and accurate assessment and significantly reduces the risk of damaging these critical assets.
The Role of Certified Locators
Given the complexities involved in accurately locating fibre optic cables, the expertise of a Certified Locator is indispensable. These professionals are trained and equipped with the latest technologies and methodologies to perform precise utility detection. Hiring a Certified Locator not only enhances safety on site but also ensures compliance with industry standards and regulations, thereby mitigating potential financial and reputational risks associated with utility strikes.
Locating fibre optic cables presents unique challenges in the field of utility detection. By integrating advanced technologies such as GPR, trace-rodding, and using sondes, along with traditional methods like careful plan study and potholing, utility locators can significantly reduce the risks associated with inadvertent strikes. Engaging a Certified Locator to oversee and conduct these activities is crucial, ensuring that every precaution is taken to protect these vital components of our telecommunications infrastructure. For projects requiring high-accuracy utility detection, South-East Scanning offers expert services that safeguard your operations against potential setbacks and financial losses. We’re excited to help you with your project – get in contact to learn more about our utility locating solutions tailored for complex and sensitive environments.
