Thermal Imaging Inspection for Package Integrity

Ensuring package sealing integrity has long been an industry challenge, one in which the stakes are exceedingly high. Hanging in the balance are quality control standards that not only mandate pharmaceutical manufacturers’ adherence to strict guidelines and low tolerances, but also
define their incalculably priceless reputations. This is, of course, because our quality control issues are a matter of public safety rather than mere product efficacy.

The primary method being used today—sampling—only allows for a percentage of packages units to be inspected. Finally, however, technology has caught up to meet pharma’s packaging integrity inspection needs. Dynamic thermal imaging allows pharma companies to inspect 100% of packaged products in a totally passive manner without ever even having to touch them. Dynamic thermal imaging ensures that every package that leaves a facility is properly sealed, thus maintaining the necessary sealing barrier to protect product efficacy.

Inspection is performed through the cap by means of high-sensitivity thermal imaging. Upon being detected any defective bottles are removed from the production line.
Inspection is performed through the cap by means of high-sensitivity thermal imaging. Upon being detected any defective bottles are removed from the production line.

Benefits of Thermal Imaging

Benefits of Thermal Imaging in the detection of:

  • Water infiltration  (roof leaks located with recent rain fall within 24~48 hours)
  • Cold air infiltration
  • Excessive moisture in building materials
  • Stud / Joist / Beam / Rafter placement and structure
  • Insulation gaps, insufficient and unevenness
  • Electrical drops, panels, breakers, switches and wire connections
  • Heating and cooling duct placement, insulation, air leaks
  • Pipe location
  • Special Inspections
    • Pest infestation
    • Energy audits
    • Insurance claims

Thermal Imaging Limitations

  • Thermal imaging only displays surface temperatures of solid objects.
  •  IR detects the temperature based upon wavelength of the light emitted by the object (longer wavelength, colder).  IR, therefore, does not show the temperature of objects that reflect light, (glass, shiny metal, light colored objects in direct sunlight).
  • IR, does not “see through walls”, but only displays the very slight differences in surface temperature of the wall.  Images of areas “behind” and not in contact with walls depends upon the temperature difference of the area.  It is easier to see “hot” objects because they will be radiating heat to the not-in-contact surface.  See pictures below for how IR is still incredibly useful.
  • Careful adjustment of the range of temperatures displayed is important to proper imaging and interpretation. (but don’t worry: I have been trained to do this).
While there is no guarantee that nothing will be missed during the visual inspection.  Thermal imaging brings me one step closer to not overlooking anything.
So you have to ask yourself:  do you want a home inspector that offers thermal imaging or risk going with one that does not?
As you study the photos below, I remind you, these images would not be visible without the aid of a thermal imaging camera.  Which is included in all my inspections!

Updated March 2018

Home owner did not know bathroom above was leaking…they do now.


 

Another ice dam found with thermal imaging.  There were no moisture signs on the ceiling, verified with a moisture meter.

How software tools can improve thermal inspection reports

Presenting a clear report of your thermal inspection and easily sharing data are just as important as getting high quality images. Sometimes it may seem that you spend more time on your report than on scanning with your infrared camera, but they work hand in hand. You want the report to be thorough and accurate

The Growth of Infrared and Thermal Imaging Solutions

infrared and thermal imaging

Infrared and thermal imaging solutions are gaining popularity in a number of applications across the globe. Early thermal imaging solutions were expensive and had to have some form of external cooling system. Today, a thermal imaging system no longer needs the bulky cooling system and is far cheaper, making them more accessible and useful in a variety of settings.

As infrared and thermal imaging solutions have become widely available, they’ve become widely utilized. They bring a number of advantages over visible imaging solutions for certain applications.

What are Infrared and Thermal Imaging Systems Used for?

Thermal and infrared imaging systems are used in a wide range of industries and applications. For example, they’re used in security settings to identify intruders, surveillance applications to monitor critical infrastructure, construction to detect flaws in a building, and agriculture to track crop health, among many other applications.

These types of cameras are often used outdoors to detect light outside of the visible spectrum. The ability to see different spectrums of light has many benefits, regardless of the application.

Benefits of Infrared and Thermal Imaging Systems

While thermal and infrared systems are deployed in a wide range of settings, there are fundamental advantages that non-visible imaging solutions have over visible imaging solutions.

Infrared and thermal imaging systems perform well in low-light and low-visibility situations. This is critical for outdoor applications where light and visibility are a constant variable, and especially useful in security applications – no camouflage will fool a thermal camera.

Infrared and thermal cameras can also be used to measure temperature differences, which is critical for monitoring critical equipment. For example, a thermal camera can monitor electrical equipment – which heats up before it fails – to signal when maintenance or replacement is required.

Thermal and infrared image systems provide great return on investment (ROI) in most applications. In the examples above, keeping a location safe and secure, or avoiding a catastrophic equipment failure, can lead to rapid ROI. Thermal and infrared cameras, with their better performance in low-light situations, often require less initial investment too, as fewer cameras can be used. All of this adds up to reliable ROI.

Infrared and thermal imaging systems have become a common solution for security, surveillance and monitoring applications, among others. Advancing technology, decreasing costs and fundamental advantages over visible imaging solutions in certain applications have all led to the growing use of infrared and thermal imaging systems.

Definition of DRI : Detection, Recognition, Identification ranges

The question the most frequently asked to thermal imager manufacturers is certainly: how far can the IR camera detect a target? It is indeed a good criterion to qualify one sensor from another considering the final application. And the answer given to this question will probably include the “DRI ranges” expression.

DRI stands for Detection, Recognition and Identification. DRI ranges, expressed in km (or miles), can be found in the specification table of infrared camera brochures. In order to select the right sensor meeting the application requirements, these DRI ranges have to be, first, perfectly defined, but also assessed with regards to globally adopted industrial standards.

DRI Definition

John Johnson, a scientist from the Army Night Vision Laboratory, was a pioneer in 1958, conducting experiments to test observers’ ability to identify targets through analog sensors. The terms “Detection”, “Recognition” and “Identification” were defined as follow:

  • Detection: ability to distinguish an object from the background
  • Recognition: ability to classify the object class (animal, human, vehicle, boat …)
  • Identification: ability to describe the object in details (a man with a hat, a deer, a Jeep …)

The following pictures illustrate these definitions:

Detection-Recognition-Identification ranges

    Left image: Detection – At several kms, 2 targets are detected out of the background 

Thermal Imaging Cameras Explained

Thermal imaging cameras are devices that translate thermal energy (heat) into visible light in order to analyze a particular object or scene. The image produced is known as a thermogram and is analyzed through a process called thermography. Thermal imaging cameras are sophisticated devices that process the captured image and display it on a screen. These images can be used for immediate diagnosis or processed through specialized software for further evaluation, accuracy and report output. Thermal imaging cameras take measuring temperature to the next level; instead of getting a number for the temperature you get a picture showing the temperature differences of a surface.

What Do Thermal Imaging Cameras See?

Visible light is what we see around us every day. It is the only part of the electromagnetic spectrum that we can see. Visible light only takes up a small area in the electromagnetic spectrum and infrared radiation (IR) represents a larger percentage. If we want to see what’s going on in other parts of the spectrum we need specialized equipment.

All objects absorb, reflect and sometimes transmit energy at different levels. Different materials will give off heat or cold energy at different rates. It’s this energy that can be detected by infrared equipment and displayed as images.

Thermal Imaging Camera Applications and Uses

How Thermal Imaging Works

All objects, both natural and manmade, emit infrared energy as heat. By detecting very subtle temperature differences of everything in view, infrared (or thermal imaging) technology reveals what otherwise would be invisible to the naked eye. Even in complete darkness and challenging weather conditions, thermal imaging gives users the ability to see the unseen.
First developed for military purposes, thermal imaging has since been adopted by law enforcement, fire and rescue teams and security professionals. For law enforcement and security staff, thermal imaging detects suspicious activity over long distances in total darkness and through fog, smoke, dust, foliage, and many other obscurants.
This allows officers to approach in stealth mode and make better informed decisions more quickly. Cameras may be handheld, vehicle-mounted, tripod-mounted, or weapon-mounted. For security and surveillance systems, thermal imaging cameras complement CCTV cameras to provide comprehensive threat detection and integrate seamlessly with larger networks. For predictive maintenance, thermal imaging reveals “hot spots” where failure may be imminent in many electrical and industrial facilities and installations. In order to understand thermal imaging, it is important to understand something about light.

IR LED | Infrared LED | Infrared Sensor

An Infrared light emitting diode (IR LED) is a special purpose LED emitting infrared rays ranging 700 nm to 1 mm wavelength. Different IR LEDs may produce infrared light of differing wavelengths, just like different LEDs produce light of different colors. IR LEDs are usually made of gallium arsenide or aluminum gallium arsenide. In complement with IR receivers, these are commonly used as sensors.

The appearance of IR LED is same as a common LED. Since the human eye cannot see the infrared radiations, it is not possible for a person to identify if an IR LED is working. A camera on a cell phone camera solves this problem. The IR rays from the IR LED in the circuit are shown in the camera.

Pin Diagram of IR LED

IR LED

An IR LED is a type of diode or simple semiconductor. Electric current is allowed to flow in only one direction in diodes. As the current flows, electrons fall from one part of the diode into holes on another part. In order to fall into these holes, the electrons must shed energy in the form of photons, which produce light.

It is necessary to modulate the emission from IR diode to use it in electronic application to prevent spurious triggering. Modulation makes the signal from IR LED stand out above the noise. Infrared diodes have a package that is opaque to visible light but transparent to infrared. The massive use of IR LEDs in remote controls and safety alarm systems has drastically reduced the pricing of IR diodes in the market.

IR sensor

An IR sensor is a device that detects IR radiation falling on it. Proximity sensors (used in touchscreen phones and edge avoiding robots), contrast sensors (used in line following robots) and obstruction counters/sensors (used for counting goods and in burglar alarms) are some applications involving IR sensors.

Principle of Working

Infrared IR Sensor Circuit Diagram and Working Principle

An infrared sensor is an electronic device, that emits in order to sense some aspects of the surroundings. An IR sensor can measure the heat of an object as well as detects the motion.These types of sensors measures only infrared radiation, rather than emitting it that is called as a passive IR sensor. Usually in the infrared spectrum, all the objects radiate some form of thermal radiations. These types of radiations are  invisible to our eyes, that can be detected by an infrared sensor.The emitter is simply an IR LED (Light Emitting Diode) and the detector is simply an IR photodiode which is sensitive to IR light of the same wavelength as that emitted by the IR LED. When IR light falls on the photodiode, The resistances and these output voltages, change in proportion to the magnitude of the IR light received.

IR Sensor
IR Sensor

IR Sensor Circuit Diagram and Working Principle

An infrared  sensor circuit is one of the basic and popular sensor module in an electronic device. This sensor is analogous to human’s visionary senses, which can be used to detect obstacles and it is one of the common applications in real time.This circuit comprises of the following components

  • LM358 IC 2 IR transmitter and receiver pair
  • Resistors of the range of kilo ohms.
  • Variable resistors.
  • LED (Light Emitting Diode).
IR Sensor Circuit
IR Sensor Circuit

IR cameras: The new tool for emission leak detection

Since the beginning of the industrial age, the world has used natural resources to enable manufacturing and production. The use of gases, and the chemicals that produce them, have been pivotal in this evolution. Unfortunately, the majority of the gases used by industry are radiatively insulating in the infrared %%MDASSML%% in other words, greenhouse gases.

The IR camera allows users to visually discern a gas in its host atmosphere. With an IR imager, one can “see” where the gas is originating, as well as where the gas cloud is traveling. One can immediately recognize the health and safety impact of this tool and the environmental implications. From first detection to eventual gas containment and even remediation, the benefits of applying this technique are vast.

On December 15, 2008, the U.S. Environmental Protection Agency issued a final amendment to its leak detection and repair requirements, “allowing the use of optical gas imaging technology to locate emission leaks. The leaks are displayed on a video screen similar to the way night vision goggles are used to show the heat signature of objects. This amendment provides requirements for using the new technology; however, facilities may continue to use existing approved work practices to detect leaks,” the EPA said in a statement at www.epa.gov .

How it works

Greenhouse gases absorb infrared light; this is what makes them greenhouse gases in the first place. The gas restricts or insulates the IR radiation from passage through the atmosphere, retaining the thermal energy inherent in the radiation. As a consequence, the air warms up and shields the earth from effectively cooling itself.