Interview Questions for Thermal Imaging and Inspection

Infrared thermography, or thermal imaging, relies on the principle that all objects above absolute zero (-273.15°C or 0 Kelvin) emit infrared (IR) radiation. This radiation is invisible to the human eye but can be detected by specialized cameras. The intensity of this emitted IR radiation is directly proportional to the object’s surface temperature. An infrared camera measures this radiation and converts it into a visual image, where different colors represent different temperature levels. Hotter objects appear brighter (often red or white), while cooler objects appear darker (often blue or black). This allows us to visualize temperature variations across a surface, revealing information that would otherwise be invisible.

Think of it like a night vision scope, but instead of seeing light reflected, we see heat emitted. This ‘heat signature’ provides invaluable information about the object’s thermal characteristics.

Infrared cameras come in various types, each suited for specific applications:

• Microbolometer cameras: These are the most common type, utilizing a microbolometer array to detect IR radiation. They are relatively inexpensive, robust, and offer good thermal sensitivity. Applications include building inspections, electrical maintenance, and industrial process monitoring.
• Cooled infrared cameras: These cameras use a cooled detector, usually a photoconductor or photodiode, which requires liquid nitrogen or other cooling systems. They are extremely sensitive, capable of detecting even minute temperature differences, making them ideal for scientific research, astronomy, and highly specialized industrial applications. The cooling increases sensitivity and reduces noise.
• Quantum well infrared photodetectors (QWIPs): These offer high sensitivity and operate at relatively higher temperatures than other cooled cameras, reducing the complexity of cooling. They are often found in applications demanding both high sensitivity and compactness.
• InSb and HgCdTe cameras: These detectors are often found in highly specialized, demanding applications needing very fast frame rates and exceptional sensitivity, such as guided missiles or high-speed industrial processes.

The choice of camera depends heavily on the application’s specific needs, balancing factors like sensitivity, resolution, cost, size, and operating temperature.

Several factors influence thermal image quality:

• Camera Resolution: Higher resolution means more detail and better accuracy in temperature measurement.
• Thermal Sensitivity (NETD): This indicates the smallest temperature difference the camera can detect. A lower NETD value means better sensitivity.
• Field of View (FOV): Determines the area the camera can see. Selecting appropriate FOV is crucial for the application.
• Emissivity: The object’s ability to emit infrared radiation (discussed in more detail later).
• Atmospheric Conditions: Humidity, temperature gradients in the air, and atmospheric attenuation affect IR radiation transmission.
• Reflected Radiation: Radiation reflected from the surroundings can contaminate the measurement.
• Distance to the Target: Distance introduces attenuation of the infrared signal, decreasing resolution and increasing the impact of other error factors.

Optimizing these factors ensures accurate and detailed thermal images. For instance, a poorly calibrated camera with high NETD may struggle to distinguish between subtle temperature differences, while atmospheric conditions can significantly obscure the view and add errors.

Interpreting a thermal image requires understanding the temperature scale and recognizing patterns. Areas of higher temperature appear brighter, often in warmer colours. Identifying potential problems involves comparing temperature readings with known values and looking for anomalies:

• Temperature Gradients: Abrupt temperature changes across a surface can indicate issues like insulation problems in buildings or overheating components in machinery.
• Hot Spots: Significantly warmer areas compared to the surroundings usually point towards potential failures or defects. A hot spot on an electrical panel, for instance, can be a sign of overheating wiring.
• Cold Spots: These indicate areas with reduced heat transfer, potentially caused by gaps in insulation or air leaks. In a pipe, a cold spot may signal poor insulation leading to heat loss.
• Uniformity: Consistent temperatures suggest proper function, whereas irregular patterns suggest defects or malfunctions. For example, uneven heating across a solar panel might mean some cells aren’t performing as expected.

It’s important to correlate thermal images with visual inspection and other diagnostic methods. A professional report generally includes visual and thermal images with detailed notes outlining the interpretations and recommendations. For example, a thermal image showing a hot spot on a motor bearing should be accompanied by a visual inspection to confirm potential damage and suggest corrective actions.

Emissivity (ε) is a crucial parameter in thermal imaging. It represents a material’s ability to emit infrared radiation relative to a perfect blackbody (which has an emissivity of 1.0). A blackbody is an idealized object that absorbs all incident radiation and emits radiation based solely on its temperature. Most materials have an emissivity less than 1.0. For example, polished metal has a low emissivity, reflecting most IR radiation, while dark matte surfaces have high emissivity and emit radiation effectively.

The emissivity significantly impacts temperature measurements. If the camera doesn’t account for the object’s emissivity, it will provide inaccurate temperature readings. For example, measuring the temperature of a polished metal pipe without considering its low emissivity will result in an underestimation of the actual temperature because a portion of the emitted radiation is reflected. Most modern cameras allow for manual emissivity adjustments, often using pre-programmed values for various materials, or by measuring the actual emissivity with other tools. Failing to properly account for emissivity can lead to misinterpretation of thermal images and incorrect conclusions.

Several sources of error can affect the accuracy and reliability of thermal imaging inspections:

• Incorrect Emissivity Settings: As discussed earlier, failing to accurately account for the target’s emissivity leads to inaccurate temperature readings.
• Reflected Temperature: IR radiation reflected from surrounding surfaces can contaminate the measurement, leading to inaccurate temperature readings. To minimize this, ensure minimal reflection by using masking techniques or selecting the proper time for inspection.
• Atmospheric Effects: Atmospheric absorption, scattering, and refraction can affect the accuracy of temperature measurements, especially over long distances.
• Calibration Errors: A poorly calibrated camera will provide inaccurate readings and affect the image quality. Regular calibration and maintenance are necessary to mitigate this.
• Ambient Temperature Changes: Significant changes in ambient temperature during the inspection can influence the readings.
• Operator Error: Incorrect camera settings, improper focusing, or misinterpretation of the thermal image can lead to errors in analysis.

Careful planning, proper technique, and thorough knowledge of the technology are crucial to minimize the impact of these error sources. A good thermal imaging professional should understand these challenges and take steps to mitigate them. Documented procedures and standardized testing protocols can improve the accuracy and reliability of thermal imaging inspections.

Calibrating and maintaining an infrared camera is crucial for ensuring accurate and reliable measurements. Calibration involves adjusting the camera’s internal settings to match known temperature values. This often involves using a calibrated blackbody source, a device that emits known amounts of IR radiation at specific temperatures.

The exact calibration procedures vary depending on the camera model and manufacturer but generally involve:

• Blackbody Calibration: Point the camera at a calibrated blackbody at various temperatures to adjust the internal temperature readings.
• Optical Alignment: Some cameras require periodic optical alignment checks to ensure accurate focusing and image quality. This is usually done by a qualified technician.
• Software Updates: Update the camera’s firmware to benefit from the latest improvements and bug fixes.

Routine maintenance includes:

• Lens Cleaning: Regularly clean the lens with a soft, lint-free cloth to prevent dust and other debris from affecting the image quality. The frequency depends on usage but can be as often as every inspection.
• Storage: Store the camera in a clean, dry environment to prevent damage.
• Regular Inspection: Before each use, perform a visual inspection of the camera for any physical damage or obvious problems.

Following the manufacturer’s recommendations for calibration and maintenance ensures optimal performance and prolongs the camera’s lifespan. Regular checks by a qualified service technician are also recommended, especially for high-value equipment used in critical applications.

A building envelope thermal inspection aims to identify areas of heat loss or gain in a structure. Think of it like giving the building a ‘thermal checkup’. We use a thermal camera to capture infrared radiation, invisible to the naked eye, which reveals temperature variations across the building’s exterior.

• Preparation: We begin by scheduling the inspection during optimal weather conditions – typically a clear, cold night for maximum temperature contrast. Wind can affect readings, so we check the forecast.
• Scanning: Using a high-resolution thermal camera, we systematically scan the entire building envelope, including walls, roofs, windows, and doors. We pay close attention to areas known for potential problems, like corners and junctions.
• Image Capture: The camera captures thermal images, displaying temperature variations as color gradients. Hotter areas appear in warmer colors (e.g., reds, yellows), while cooler areas appear in colder colors (e.g., blues, purples).
• Analysis: We analyze the images, looking for anomalies like unusually warm or cold spots, indicating potential thermal bridges, air leaks, or insulation deficiencies. For example, a consistently warmer section of a wall might reveal inadequate insulation, while a cold spot around a window suggests air infiltration.
• Reporting: We generate a detailed report including thermal images with annotations highlighting problem areas, along with recommendations for remediation. This might include adding insulation, sealing air leaks, or repairing damaged window frames.

Electrical overheating is a significant fire hazard, and thermal imaging is an excellent tool for detecting it before it escalates. Overheated components emit more infrared radiation than their surroundings, showing up as hot spots in the thermal image.

• Identifying Overheating: We scan electrical panels, wiring, and equipment, looking for areas significantly warmer than their surroundings. For example, a connector with a temperature significantly higher than adjacent wires is a red flag.
• Context is Key: It’s crucial to understand the normal operating temperature of the equipment. What might seem hot to an untrained eye might be normal operating temperature for a specific component. We always consult the manufacturer’s specifications.
• Example: Imagine inspecting a large electrical panel. We might find a specific circuit breaker significantly hotter than others. This suggests an overload or a faulty connection, potentially leading to a fire if left unaddressed.
• Further Investigation: Thermal imaging provides initial indications; follow-up inspections with more detailed electrical testing are often necessary to confirm the diagnosis and determine the cause.

Predictive maintenance uses thermal imaging to identify potential problems *before* they cause costly downtime or equipment failure. Instead of reacting to failures, we proactively address them.

• Early Detection: Thermal imaging allows us to detect subtle temperature variations that might indicate developing problems, such as bearing wear, insulation degradation, or loose connections. For instance, a slightly warmer motor bearing compared to others in a similar system could suggest impending failure.
• Prioritization: By identifying potential issues early, we can prioritize repairs and maintenance, maximizing resource allocation. We focus our efforts on critical equipment that is exhibiting early signs of failure rather than reacting to catastrophic failures.
• Cost Savings: Predictive maintenance reduces the likelihood of catastrophic failures, saving money on repairs, replacements, and lost productivity. A small intervention early is far cheaper than a complete machine overhaul.
• Example: In a manufacturing facility, we could regularly inspect motors and gearboxes with thermal imaging. By spotting subtle temperature increases, we can schedule maintenance before a catastrophic failure shuts down the production line.

Safety is paramount during any thermal inspection. We adhere to strict protocols to protect ourselves and others.

• Personal Protective Equipment (PPE): Appropriate PPE includes safety glasses, gloves, and flame-retardant clothing when working near high-voltage equipment. We use specialized clothing when working in hazardous environments.
• Lockout/Tagout Procedures: When working near electrical equipment, we follow strict lockout/tagout procedures to prevent accidental energization. This involves de-energizing the system and physically locking it to prevent accidental power restoration.
• Awareness of Surroundings: We are always aware of our surroundings and potential hazards, such as uneven terrain, obstacles, and potential fall hazards. We use appropriate safety harnesses and other fall protection equipment as necessary.
• Working at Heights: When performing inspections on rooftops or elevated areas, we utilize appropriate fall protection systems, following all relevant safety regulations and using secured scaffolding if needed.
• Environmental Conditions: We adjust our procedures based on the environment, considering factors like temperature extremes, precipitation, and wind. We work with appropriate lighting and maintain a safe distance from any hazards.

Analyzing thermal data involves interpreting the thermal images and creating a comprehensive report. This process is both qualitative and quantitative.

• Image Review: We carefully examine the images for temperature differences and patterns. We compare temperatures to baseline values and manufacturer specifications.
• Quantitative Analysis: We use the software to measure temperatures at specific points and determine the temperature differences between areas. Software calculates isotherms and automatically identifies hot/cold spots.
• Qualitative Assessment: We interpret the data in the context of the building or equipment being inspected. We identify potential problems, such as air leaks or insulation deficiencies, and assess their severity.
• Report Generation: We create a comprehensive report that includes annotated thermal images, temperature measurements, and a detailed description of the findings. The report provides clear recommendations for repairs and remediation.
• Example: We might include an image of a wall with a large cold spot, along with the measured temperature, a comparison to the surrounding wall temperature, and a recommendation for increased insulation in that specific area.

I am proficient in several software packages for thermal image analysis, including FLIR Reporter, ThermaCAM Researcher, and IRBIS.

• FLIR Reporter: This is a widely used software for creating detailed reports, including annotations and measurements directly on the thermal images.
• ThermaCAM Researcher: This software offers more advanced analytical features, allowing for more complex data analysis and reporting.
• IRBIS: This software is specifically designed for industrial applications, often used for predictive maintenance and advanced analysis.

My expertise extends beyond specific software to include understanding the underlying principles of thermal analysis and applying the right tools for the specific situation.

The difference lies in how the object being imaged interacts with infrared radiation.

• Emissive Thermal Imaging: This is the most common type. It measures the infrared radiation emitted by an object itself due to its temperature. The hotter the object, the more infrared radiation it emits. Think of a glowing hot coal; it emits its own infrared radiation.
• Reflective Thermal Imaging: This measures the infrared radiation reflected by an object from another source. It’s like taking a picture of a mirror reflecting a light; you see the reflection, not the mirror’s inherent temperature. This is less common in building inspections but can be useful in specific applications, such as detecting sources of reflected heat.

In most building inspections, we primarily use emissive thermal imaging to assess the building’s inherent thermal properties. However, understanding reflective thermal imaging is important to interpret data accurately and avoid misinterpretations.

My experience with thermal imaging spans various sectors, encompassing electrical, mechanical, and building inspections. In electrical systems, I’ve used thermal cameras to identify overheating connections, faulty circuit breakers, and overloaded circuits, preventing potential fires and equipment failures. For example, I once located a loose connection in a high-voltage panel that was generating significant heat, only detectable via thermal imaging, preventing a catastrophic failure. In mechanical applications, I’ve inspected bearings, motors, and gearboxes for excessive friction and wear, identifying potential mechanical failures before they occur. This included detecting early signs of wear in a critical pump bearing in a manufacturing plant, leading to timely maintenance and avoiding costly downtime. Finally, in building inspections, I’ve identified insulation deficiencies, air leaks, and moisture problems, improving energy efficiency and preventing structural damage. A recent project involved pinpointing water intrusion behind a wall using thermal imaging, leading to efficient and targeted repairs instead of costly demolition.

Selecting the appropriate temperature range is crucial for optimal image interpretation. It depends on several factors, primarily the expected temperature of the target and the ambient temperature. I typically start by considering the material being inspected; for instance, electrical components might operate within a 30°C to 100°C range, while building inspections may focus on a wider range, say 0°C to 40°C to detect temperature variations indicating insulation problems. The ambient temperature is also factored in; on a hot day, the overall temperature will be shifted, necessitating adjustments. Many thermal cameras allow for setting temperature ranges pre-inspection and then adjusting the range during inspection, using tools like the span adjustment to highlight subtle temperature differences, particularly crucial in low-contrast scenarios.

Relative humidity plays a significant, often overlooked, role in thermal imaging. High humidity can affect the emissivity of surfaces, leading to inaccurate temperature readings. Emissivity refers to a material’s ability to emit infrared radiation. For example, a damp surface will have a different emissivity than a dry surface, resulting in a lower apparent temperature. This is particularly problematic when inspecting materials with variable moisture content, like wood or concrete, in building inspections. To mitigate this, I often take into account weather conditions and use emissivity correction features available on advanced thermal cameras to compensate for humidity’s influence on readings. Understanding and addressing humidity’s effect ensures more accurate and reliable thermal data.

Poor thermal contrast can be challenging but can often be improved using several techniques. First, I check for environmental factors influencing the images like wind, sunlight, or radiative heat sources. Adjusting the camera’s settings, like increasing the gain or altering the temperature range, can enhance contrast. Software tools often include features like level and span adjustments which are invaluable in adjusting the display of the thermal image, creating optimal contrast between areas of interest. Furthermore, using thermal image processing software allows for more advanced manipulations like adjusting colour palettes and applying filters to further enhance contrast. If contrast remains poor after these methods, I often need to consider additional environmental controls or re-examine the inspection strategy.

Thermal gradients, which are the rate of temperature change over a distance, are extremely important in identifying anomalies. Sharp thermal gradients often indicate problems. For instance, a sudden temperature drop along a pipe may signal poor insulation or a leak. Similarly, a localized hot spot on an electrical panel indicates a possible fault. The size and steepness of the thermal gradient provide valuable clues about the nature and severity of the anomaly. For example, a small, but steep, gradient might indicate a localized fault, whereas a larger, gradual change might signal a more widespread issue. Understanding these thermal gradients is key to accurate anomaly identification and prioritization for repair or replacement.

My experience includes using various thermal image analysis software packages. These include both manufacturer-specific software and more general-purpose image processing tools. Manufacturer-specific software often provides tools tailored to the specific camera model and its capabilities. This can include advanced features such as emissivity correction, temperature profiling, and report generation. General-purpose image processing software provides more flexibility and allows for extensive image manipulation, such as creating detailed reports or integrating thermal data with other inspection data. I’m proficient in utilizing these tools for advanced analysis, creating detailed reports, and drawing meaningful conclusions from the thermal data to support decision-making.

Ensuring accuracy and reliability involves a multi-faceted approach. First, I always perform a thorough camera calibration before each inspection to verify the accuracy of its temperature readings. This involves using a calibrated blackbody source to establish a reference point. Second, understanding the emissivity of the target material is critical. I utilize emissivity tables and adjustments to compensate for differing surface properties. Third, appropriate environmental conditions are considered; wind, direct sunlight, and other sources of radiant heat can skew results. Finally, I use multiple image capture methods and techniques to minimize potential errors, and always maintain detailed records of all settings and environmental conditions during an inspection. These steps, along with careful post-processing and image analysis, significantly enhance the accuracy and reliability of the thermal imaging results.

Thermal imaging standards and codes ensure consistent data acquisition, analysis, and reporting. Different industries and applications have specific requirements. For example, ASTM (American Society for Testing and Materials) provides several standards relevant to infrared thermography, like ASTM E1933 for building inspections. These standards cover various aspects such as camera calibration, image acquisition procedures, interpretation of thermograms, and reporting requirements. Other relevant standards come from organizations like ISO (International Organization for Standardization) focusing on aspects like quality control and terminology.

• ASTM E1933: This standard covers the procedure for performing infrared inspections on buildings to detect heat loss or gain. It defines parameters like emissivity settings, ambient temperature measurements, and reporting requirements.
• ISO 18436-1: This is a series of standards outlining the qualification standards and certification of thermographers, ensuring competency and adherence to best practices.
• Industry-Specific Codes: Beyond general standards, specific industries (e.g., electrical power, manufacturing) have their own codes and guidelines that dictate acceptable practices and reporting formats for thermal inspections. For example, electrical inspection codes might detail necessary checks for overheating electrical equipment based on temperature thresholds.

Understanding these standards is crucial for maintaining accuracy, reliability, and defensibility of thermal inspection reports. Ignoring these standards can lead to inaccurate findings, missed defects, and legal issues.

Troubleshooting a malfunctioning infrared camera requires a systematic approach. I’d start with the most obvious issues before delving into more complex problems.

1. Check Power and Connections: Ensure the camera is properly powered and all cables are securely connected. A loose connection is a common culprit.
2. Verify Lens and Window: Clean the lens and the protective window on the camera. Dirt, dust, or moisture can significantly affect image quality and performance.
3. Examine the Display and Settings: Check if the camera display is working properly and review the settings (focus, emissivity, distance, etc.) to ensure they are accurate for the inspection. A misplaced setting can lead to inaccurate readings.
4. Test with a Known Good Target: Use a calibrated blackbody source or a known-temperature object to assess if the temperature readings are accurate. This helps rule out sensor or calibration issues.
5. Check Software and Firmware: Ensure that the camera’s firmware is up-to-date and the accompanying software is functioning correctly. Outdated software might not have essential bug fixes.
6. Inspect for Physical Damage: Examine the camera for any signs of physical damage, including cracks or dents, which might affect sensor integrity.
7. Seek Professional Support: If the problem persists after these steps, contacting the camera manufacturer or a qualified service technician is necessary.

For instance, I once encountered a situation where an infrared camera displayed abnormally low temperatures. After systematically checking the above steps, I discovered that the lens was slightly out of focus, causing a blurring of thermal data. Correcting the focus resolved the issue.

Effective communication is paramount in thermal imaging. My approach involves tailoring the communication to the audience. When presenting to clients, I use clear, concise language, avoiding jargon. Visual aids such as annotated thermograms with clearly marked areas of concern are crucial. I provide a detailed explanation of each finding, its severity, and potential implications. I also offer recommendations for remediation, always focusing on practical and cost-effective solutions. For management reports, I emphasize the quantifiable aspects, including cost savings associated with preventing potential failures or quantifying energy losses.

• Visual Aids: Annotated thermograms are essential. I use color palettes, arrows, and text annotations to highlight specific areas of interest.
• Plain Language: Technical terms are explained in easily understandable language.
• Severity Levels: I use a clear system to classify findings based on their potential risk (e.g., critical, major, minor).
• Recommendations: I provide practical and cost-effective recommendations for addressing identified problems.

For example, when presenting findings to a building manager, I’d highlight energy losses through poor insulation, showing the exact areas and calculating the estimated annual savings from remediation. When presenting to an electrical engineer, I’d focus on temperature readings and potential overheating risks in electrical equipment.

Reporting and documentation in thermal imaging are meticulously done. Every inspection follows a standardized procedure. My reports include a detailed description of the inspection methodology, equipment used, environmental conditions, and relevant images. Each finding is clearly documented with specific location, temperature readings, and severity level. I maintain a robust filing system with original images, processed thermograms, and reports for easy retrieval and future reference. Using specialized software for thermal image analysis and report generation significantly helps in creating comprehensive, well-structured documents.

• Inspection Methodology: Detailed description of procedures followed, including camera settings and calibration.
• Environmental Data: Ambient temperature, humidity, and wind speed are recorded.
• Image Data: Original and processed thermograms are stored, along with detailed image annotations.
• Findings Summary: Clear identification of all findings, including location, temperature readings, and severity level.
• Recommendations: Actionable recommendations are provided based on the severity of findings.

I’ve used various reporting software that integrate with thermal camera systems, enabling seamless data transfer and automated report generation. This guarantees consistency in reporting and simplifies the documentation process. Maintaining a detailed record is crucial for compliance, insurance purposes, and for tracking maintenance activities.

Staying current in this field necessitates continuous learning. I actively participate in industry conferences and workshops, attending seminars and training sessions to learn about new technologies and techniques. I subscribe to relevant professional journals and online publications, and I’m a member of professional organizations like the Infrared Training Center (ITC). I regularly review new camera models and software updates, comparing the features and capabilities of various technologies. This ensures that my skills and knowledge remain cutting-edge and I can effectively utilize the latest advancements in my work.

• Industry Conferences and Workshops: Attending events to learn about new technologies and best practices.
• Professional Journals and Publications: Keeping updated on latest research and development in thermal imaging.
• Professional Organizations: Networking with other professionals and staying informed about industry trends.
• Online Resources: Utilizing online resources for tutorials, webinars, and information from equipment manufacturers.

For example, I recently attended a workshop on drone-based thermal imaging, expanding my capabilities to perform inspections in hard-to-reach areas. This continuous improvement in skills ensures that I deliver the highest quality services to my clients.

One challenging inspection involved identifying the source of a recurring electrical fault in a large industrial plant. The equipment was spread across a vast area, making it difficult to pinpoint the problem. The high ambient temperatures complicated the inspection, making it hard to differentiate between normal operating temperatures and actual overheating. To overcome this, I employed a multi-pronged approach.

1. Phased Inspection: I divided the inspection into smaller, manageable sections to focus on critical areas.
2. Multiple Data Sets: I took measurements at different times of the day to account for fluctuating ambient temperatures.
3. Advanced Software: I used specialized software to analyze the thermographic data, applying algorithms to filter noise and enhance signal-to-noise ratio.
4. Collaboration with Engineers: I collaborated with the plant engineers to understand the system’s layout and operation, ensuring accurate interpretation of the thermal data.

Through a combination of careful planning, advanced software techniques, and effective collaboration, I successfully identified the faulty components. This demonstrated the value of a methodical and adaptable approach in complex inspections.

Thermal imaging, while powerful, has limitations. It’s essential to be aware of these to avoid misinterpretations. The key limitations include:

• Surface Emissivity: Different materials have different emissivities (ability to emit infrared radiation). If the emissivity is not correctly accounted for, temperature readings can be inaccurate. For example, a highly reflective surface like polished metal will appear colder than it actually is.
• Reflected Temperatures: The camera might detect reflected thermal radiation from surrounding objects, leading to inaccurate temperature readings. This is particularly problematic in environments with significant temperature gradients.
• Atmospheric Conditions: Humidity, temperature gradients, and other atmospheric conditions can affect the accuracy of temperature measurements, especially over longer distances.
• View Obstructions: Anything obstructing the line of sight between the camera and the target will prevent accurate temperature measurement. This includes dust, moisture, or other physical barriers.
• Limited Depth Penetration: Infrared radiation does not penetrate many materials effectively. For example, it cannot detect internal defects within a thick wall.

Therefore, a thorough understanding of these limitations is critical for accurate interpretation and reporting. Mitigation strategies, such as using appropriate emissivity settings, considering reflected temperatures, and ensuring a clear line of sight, are important to overcome these limitations.