Why do some things glow when they are hot?

May 25, 2016By Bob BerryGeneral

Objects begin to glow when they become incandescent. Incandescence is a name given when objects begin emitting thermal energy in the visible part of the electromagnetic spectrum. This usually starts at about 500-525 degrees C. As an object heats up two things happen. Firstly they emit more radiated energy. Secondly, the peak wavelength of the … Read More

Will a silvered mirror have a high or low emissivity?

May 15, 2016By Bob BerryGeneral

This is an excellent question. A silvered mirror is a piece of glass, coated on one side with a very reflective metal. The silvered side with have an extremely low emissivity, but the other side is essentially glass, so its emissivity will be the emissivity for the glass, which should be high. Sometimes people use … Read More

What is temperature?

May 13, 2016By Bob BerryGeneral

  An excellent question, the concept of temperature relates to the average speed of molecular movement. It is a relative measurement, letting us know simply that one object is hotter (or colder) than another object. The principle of temperature measurement is essentially linked to the so-called “Zeroth Law of Thermodynamics”. This curiously named law is … Read More

CUI Classification with thermography

May 11, 2016By Bob BerryGeneral

What priority classification should be used for CUI (corrosion under insulation) thermography inspections? CUI is more difficult to classify than electrical thermography. There are many criteria that affect the likelihood of corrosion, including condition of insulation, operating temperature, and surface protection. To classify the risk based on temperature is normally done as follows*; High between … Read More

Can I skip Level 1 thermography & move directly to Level 2?

May 9, 2016By Bob BerryGeneral

I have been asked this again. In short the answer is maybe, it depends, but it is not recommended. ISO 18436 does make allowances for previous learning and permits people to move directly to Level 2 in certain circumstances. Every case is really assessed individually. It is likely that if you recently completed a degree … Read More

Certification issues

May 8, 2016By Bob BerryGeneral

I am often asked by student to explain the difference between ASNT and ISO certification systems. Proper certification is pure written proof of qualification. So while I agree very much that you can be competent without certification, this is not to say that certification has no value. There are various types of certification; 1 Training company … Read More

Make Thermal Imaging Camera from a Webcam

May 6, 2016By Bob BerryGeneral

Yet again I am faced with the question “How can I make a thermal imaging camera from a Webcam?” I am often asked this, and in particular if the webcam can be converted to work as a thermal imaging camera. The answer to this is that you cannot make a true thermal imaging camera from a webcam. … Read More

Training or experience?

April 21, 2016By Bob BerryGeneral

I am often asked which is more important, training or experience? I can only really answer this from my own point of view, and this is heavily influenced by my background in the electrical and thermography industries. Some people will argue that training is more important as you cannot gain experience without training. There are … Read More


April 18, 2016By Bob BerryGeneral

What is emissivity? Emissivity describes an objects ability to radiate energy. Some objects have a high emissivity, these are typically non metals. Other objects have a low emissivity, these are generally metallic. Emissivity of a material is a value between 0 and 1. A blackbody would have an emissivity of 1, this means that it emits … Read More