In the space of just a few years, there has been a massive escalation in demand for thermal imaging in building science. There are many reasons for this not least of which is the technology’s eminent suitability for visualising energy loss and the structural faults that cause it, as Jon Willis, ITC Manager, EMEA for Flir Systems explains.
The use of thermal imaging, alone, or in combination with other methods such as a blower door, speeds up the works considerably, pinpointing the sources of energy. It is non-invasive, non-destructive and it provides visual evidence that rectification work needs to be undertaken. This all adds value to any business, enabling anyone involved in building maintenance to demonstrate the status of the structure, pre and post-repair.
The technology is also suitable for many other applications in the built environment assuring quick return on investment. Missing insulation and delaminating render are easy to spot with a thermal imaging camera and it’s also ideal for seeking out moisture and areas prone to mould growth.
Thermal bridges are easy to spot as are leaks in flat roofs and under-floor water pipes. Another important application area is monitoring the drying of buildings, either post construction or after water damage.
The growth in thermal imaging across all industrial sectors has also resulted in the technology being much more affordable. Manufacturing economies of scale mean that an entry level camera is now less than £800. Whilst this won’t buy an infrared camera that is capable of producing a detailed image for analysis, this ‘point-and-shoot’ model will provide a good introduction to this supremely flexible technology.
Today’s thermal imaging cameras also feature increasingly sophisticated user interfaces that make them very easy to use. Set-up is often automatic and one click will save the image in a variety of modes, complete with embedded thermal data for subsequent analysis.
The trend is good news for the industry at large as the benefits of the technology are now reaching more building service engineers. But, as the technology is now so easy to apply, the need for formal training is even greater. Without a fundamental knowledge of the science behind thermal imaging, results are virtually meaningless and are at risk of serious misinterpretation.
Need for training
Training ensures that the user gets the best return on the camera investment and that application standards are upheld. For this purpose, courses are available from a choice of providers which range from foundation through to professional.
Flir Systems, for example, runs courses based on the collective experience of thermographers worldwide and these learning objectives are part of the company’s ISO compliant quality control system. Flir Level I and Level II thermography courses have also been validated by the British Institute of Non-Destructive Testing (BINDT). So the structure of these courses provides a good illustration of what the industry expects at each level.
What do the qualifications mean?
Any good supplier of thermal imaging cameras will provide a basic level of operational training and they will also recommend the user takes a foundation course. These are aimed at those who are new to thermal imaging and designed to provide a good basis for further study. They may also be application specific, for example, focusing on HVAC, electrical or building inspection.
The next qualification stage is Level I which instructs the camera user to perform industrial thermographic measurements and fundamental infrared thermography, including basic image post processing according to established and recognised procedures. This includes the use of measurement tools, emissivity adjustments and span and scale adjustments.
At this point the thermographer can use the equipment without knowing too much about its inner workings and perform uncomplicated measurements following existing routines. He or she will be able to detect obvious faults, recognise possible errors in measurement and carry out post processing and data collection.
The emphasis at this level is on hands-on training. Theory is kept as simple as possible and use of formulas is minimised.
Expansion of this knowledge base is the purpose of the higher level qualifications. They include more theory and go deeper into the physical laws that the thermal imaging camera uses to generate an image and measure temperature. They also explore the causes, anomalies and patterns that are commonly encountered in thermal imaging.
The student uses more formulas and is expected to perform simple calculations. Steady state and transient mechanisms are examined in greater detail and the course work typically involves more practical experimentation.
For any professional thermographer, Level III certification is the gold standard. It signifies wide experience and a standard of knowledge that meets internationally recognised criteria.
Assuring thermal imaging procedures are consistent and measurable is important for any company but the need for accredited training extends beyond that. Insurance companies currently require non-invasive technology to be used for diagnosing claimant’s problems and will, in the future, undoubtedly require those using thermal imaging to be properly qualified to undertake this work. So now is the time to act.