Ground-penetrating radar (GPR) is an incredibly useful tool for construction and maintenance projects, but many misconceptions exist about what it can and can't do. Let's set the record straight by debunking some of the most common myths about GPR.
1st Myth: GPR Can See Through Everything
One of the most widespread misconceptions is that GPR can “see through” anything, from solid rock to thick concrete slabs. While GPR is beneficial for detecting subsurface objects, it’s not an X-ray. The effectiveness of GPR is highly dependent on the material being scanned. For example, highly conductive materials, like metal or wet clay, can scatter or absorb signals, making it more difficult to achieve precise results. At South-East Scanning, we always explain to clients that GPR is limited, especially in highly conductive soils or dense materials.
2nd Myth: GPR Always Provides Instant, 100% Accurate Results
GPR is a fantastic tool, but it requires interpretation by a trained technician. The data collected needs to be processed and analysed to identify objects correctly. This doesn’t happen instantly on-site, and while GPR provides real-time data, it’s not a “magic wand” that guarantees 100% accuracy every time. Our technicians are well-trained in reading and analysing GPR data, ensuring we provide the most accurate results possible.
3rd Myth: GPR Can Always Detect Utilities
While GPR is excellent for detecting utilities such as pipes or cables, it’s not foolproof. The depth and material of the utility, along with ground conditions, can affect detection. Non-metallic utilities, like PVC or plastic pipes, can be especially tricky, particularly if buried deep or in moisture-heavy soils. That’s why we often combine GPR with other locating tools to get a complete picture.
4th Myth: GPR Is Only Useful for Utility Locating
Many people think GPR is only used to find utilities. The truth is that GPR has a wide range of applications in construction, including detecting voids, determining concrete thickness, and locating rebar or post-tension cables.
5th Myth: GPR Data is Self-Explanatory
Another common misconception is that the data produced by GPR units is easy to understand without expertise. This isn’t true. GPR data appears as waveforms and radargrams that require interpretation by a professional. Without the proper training and experience, it’s easy to misinterpret what you’re seeing. That’s why at South-East Scanning, we focus on collecting high-quality data and providing clear, accurate reports created by our highly trained technicians that are easy for clients to understand.
6th Myth: GPR Can Accurately Determine the Exact Depth of Objects
While GPR is excellent for identifying the depth of objects, factors like soil moisture content and the type of material being scanned can affect depth accuracy. The signal travels at different speeds through different materials, so depth estimations require calibration and expertise. Our technicians at South-East Scanning ensure that all depth readings are as accurate as possible, using a combination of tools and techniques to verify our results.
7th Myth: GPR Can Be Used Anywhere, Anytime
Though GPR is versatile, there are some conditions where it is less effective. For example, very wet or saturated soils can limit the penetration depth of the radar signals, making it harder to locate utilities or objects underground. In regions with a high water table, like certain areas of Brisbane and the Sunshine Coast, alternative methods may be required to complement GPR.
8th Myth: Anyone Can Use a GPR Scanner Without Special Training
Another major misconception is that anyone can grab a GPR scanner and start locating utilities or structures. The reality is that GPR requires specialised training to operate correctly and interpret the data accurately. Without proper knowledge, operators can easily misidentify objects or misinterpret depth and material types, leading to costly mistakes. At South-East Scanning, we emphasise the importance of training our technicians thoroughly in both the equipment and the interpretation process to ensure high-quality, reliable results on every job.
Conclusion
Ground-penetrating radar is a powerful tool, but it’s essential to understand its limitations and capabilities. At South-East Scanning, we combine GPR with expertise and clear communication to ensure clients get the most accurate, actionable information from their scans.
How do you ensure the accuracy of your GPR reports? Do you rely on experienced technicians or use software to assist in your interpretations?
