Thermal anomalies are not always as obvious as one might expect. Often, subtle thermal differences can be indicative of major problems. Because infrared thermography is a visual inspection technique, its effectiveness relies on the observation skills of the thermographer. Like any visual inspection technique, a thermographer must actively concentrate on the imagery displayed by their thermal imager.
Contrary to popular belief, humans are not inherently effective observers. Because humans tend to be casual in their observations, they frequently overlook subtleties. Whenever imaging, a thermographer’s eyes should always visually scan the monitor left to right and up and down while asking him/herself the following three questions:
What am I seeing?
Why am I seeing this?
Is this normal/reportable?
While this approach may sound cumbersome at first, this practice will soon become instinctive and can help prevent you from overlooking the subtle thermal patterns that can be indicative of serious problems.
Splash Protection for Your Imager
Taking your infrared imager into dusty or wet environments can have disastrous consequences for your imager. While it is best to wait for such conditions to subside, you can use a polyethylene sheet or trash bag to temporarily protect your imager and accomplish a qualitative inspection.
Since not all imagers and trash bags are created equal, you can use the following steps to ensure good results.
1. Set up imager looking at thermally stable target with a high emittance. If using an imaging radiometer, note the apparent temperature of the target
2. Select a clean, unused, polyethylene trash bag with a uniform thickness
3. Open trash bag and place over imager
4. Arrange a single layer of the bag to cover the lens using a rubber band to keep the plastic smooth and wrinkle free over the imager lens
5. Image target in Step 1 again and note the image quality and apparent temperature
6. Repeat above steps using different brand bags and thicknesses until you find a bag that gives minimal attenuation of image and apparent temperature
7. After selecting the bag that works best, trim to fit imager so as to prevent a tripping hazard. If your imager requires air cooling, leave the bottom of the bag open so the imager can ‘breathe’
CITA Offers Free Membership to Infraspection Grads
The Certified Infrared Thermographer’s Association (CITA) is currently offering free Affiliate membership to all graduates of the Infraspection Institute Certified Infrared Thermographer® program. Individuals may apply for membership at no charge by visiting the CITA website.
CITA provides a number of benefits for its members. The CITA online forum provides thermographers with a portal for accessing technical support, application support, thermographer registrar, opportunities for promotion and advertising, as well as keeping members up-to-date with the latest industry information and trends.
CITA’s certification program provides thermographers with access to ISO certification. Regularly scheduled training events provide additional opportunities for ongoing professional development.
Infraspection Institute is pleased to announce an early registration bonus for exhibitors at its annual IR/INFO Conference. Exhibitors that register and pay for their booth prior to September 15 are eligible to bring a second person at no additional charge. Valued at $495, this bonus provides full conference access, conference proceedings, and a tuition voucher redeemable for a discount on an Infraspection Institute Certified Infrared Thermographer® training course.
Now in its 26th year, IR/INFO is the original Advanced Infrared Training Conference, Technical Symposium and Technology Expo. IR/INFO features four days of networking, learning, and fun in a relaxed, yet professional, family atmosphere. IR/INFO is scheduled for January 18 – 21, 2015 in New Orleans, LA.
IR/INFO is a must attend event for all manufacturers and distributors of infrared equipment, condition based monitoring tools and services, reporting software, and those who provide products or services of interest to thermographers.