• Determine what you want surveyed.

• Select a qualified, experienced inspector. 

• Weigh the advantages of using a digital infrared video camera rather than an infrared gun. 

• Understand the preparations that need to be made for a survey and items to remember after the survey is complete.

• Expect a detailed assessment of the findings with accompanying images and recommendations.

A.      Electrical: incoming power service down to control cabinets

B.      Mechanical: bearings on fans, motors and line shafts

C.      Energy losses: steam traps, degraded insulation of boilers and kilns  

Many think that doing an infrared survey is much like taking a photograph. That’s not true. A qualified and certified inspector should conduct an infrared survey. It’s important to know the qualifications of anyone who conducts a survey of your property. Select a professional infrared thermographer who has a minimum of the following:

A.      Written Practice program that meets the recommended practices section, SNT-TC-1A, of The American Society of Nondestructive Testing, Inc.

B.      Program that is audited by a third party.

C.      Ability to provide reports in hard copy, as well as electronically.

D.      References on request.

The American Society for Nondestructive Testing, Inc., a nationally recognized organization that oversees all disciplines of nondestructive testing, has established recommended practice for thermal/infrared testing. This thermal/infrared testing method, designated by the society as practice number SNT-TC-1A, involves several phases that qualify an inspector for certification at two levels. These steps include:

• Forty hours of classroom study for each level of training.  Students must pass a test on those topics covered in classroom studies.
• Successful completion of an exam that tests knowledge of theory and demonstration of practical skills. This exam is administered in addition to class time.
• Monitored and documented on-the-job work experience for each level of training.
• Every inspector must follow a “written practices program” that outlines his/her qualifications, certifications, training, experience and examinations taken.  Ideally, the written practices program should be monitored by a neutral third party.

Hartford Steam Boiler exceeds the requirements

Hartford Steam Boiler believes that proper training and certification is essential to perform infrared surveys that offer customers value. We use a third party, Snell Infrared, to audit our program. Our thermographers are full-time employees with five to 15 years of experience conducting surveys in various businesses. Hartford Steam Boiler has worked extensively in North America, the Caribbean, United Kingdom, Europe and Southeast Asia.

As a preventive maintenance and loss prevention tool, video cameras have wide application in both electrical and mechanical evaluation and monitoring. Their accuracy, speed, ease-of-use, and increased safety make infrared video cameras the equipment of choice.

Video infrared cameras have several advantages:

• Accuracy
• Speed, safety, and ease of use
• Ability to detect reflective conditions
• Ability to provide a permanent record of the conditions observed

Accuracy using a “scan gun,” however, is dependent upon examining as small an area as possible. This means placing the gun as close as possible to the area being evaluated.

When a gun is placed far away from the area being evaluated, the thermographer is forced to average the results, which can negatively impact the accuracy of the survey. The only way to avoid “missing” potential hot spots is to minimize averaging by placing the gun as close as practical (and as safe as possible) to the object being surveyed.  . 

A scan gun, however, must be kept as close as possible to the area being evaluated. It is not possible to accurately evaluate more than one connection or section of conductor. This makes the process extremely time consuming when attempting to evaluate large numbers of connections and lengths of conductors.

From a safety standpoint, the infrared scan gun requires close-in work near fully loaded circuits, increasing the exposure of personnel to serious conditions.

Ability to detect reflective conditions. An infrared scan gun cannot easily differentiate between a reflected source of heat and a direct source. A digital infrared video camera, on the other hand, gives the user the ability to view the thermal image from different angles and remove the impact of reflective heat sources by moving the video camera or shielding the area being evaluated.

A digital video camera provides a digital display of the temperature at the crosshair or center of the screen, as well as a still image of the adverse condition. Many video cameras provide “side by side” infrared and full color images for ease of finding the trouble spot.

Fig. 1- Typical infrared video camera image with accompanying full-color image of the trouble spot.

• Establish what the report content will consist of and when you should expect a report to be produced and delivered.

Day of the survey:

• When the thermographer arrives at your facility, hold a short meeting to clarify the importance of safety and the route that will be taken to conduct the survey.
• The electrical load should be as near as possible the normal level when surveying electrical breakers, relays, controllers, etc. Low loads may not show problems.
• Most infrared thermographers require the customer provide a qualified person to open and close electrical panels and cabinets. Make sure your personnel can perform this task safely.
• Time is money, so proper support in opening and closing panels can assist in using the thermographer's time and skills to the fullest.

After the survey:

• Talk to the thermographer before he/she leaves your site to be certain that you are clear about what was found.
• Consider having the thermographer return after repairs are done to conduct another survey to ensure repairs were properly completed.  

HSB provides a report that goes beyond what the camera records. Our customers receive detailed assessments of the findings, infrared photos of all equipment surveyed, and insight into how certain situations may result in costly damage and/or downtime.

The report contains a detailed analysis of each piece of equipment evaluated.  The criteria used to categorize the findings are based on the potential effect that a failure will have on operations or production. Survey results for each piece of equipment are identified as:

“Critical:”  Component failure will have significant impact on production, require costly repairs, and represents a potential personnel hazard.

“Severe:” Failure is not expected to go beyond this particular piece of equipment and should have relative minor impact on operations and production. 

“Alert:”  Failure is of a routine nature and repairs can be easily made.

A sample report can be viewed by downloading a PDF file.  You will need Adobe Acrobat reader to view the file.  If you do not have this software, click here to download it.