NOTICE: IRMI is in the process of transitioning to a new website. As of 8/3/2015, this website is no longer being updated.
To get the current information in your subscription visit the new website at preview.irmi.com.
The problem faced by most property owners
is that moisture behind walls, over ceilings, and under floors is often impossible
to detect until the problem is excessive and visible to the naked eye. Since
the investigation and removal of infestations of not yet visible, mold in structures
is often difficult, technology is now being used to do what once was impossible.
Barry Zalma Inc.
According to the U.S. Environmental Protection Agency, there is no practical
way to eliminate mold spores in an indoor environment. The best way to control
mold growth is to control moisture. Mold can begin growth in as little as 24
hours. Roof leaks and water pipe leaks are common sources of water accumulation
that may cause mold growth.
Technology has provided a tool that can be used by investigators, remediators,
and consultants to detect and help eliminate mold infestations. The technological
tool is called Infrared Thermography (IT). IT is a technique that produces an
image of invisible (to the human eye) infrared light emitted by objects due
to the heat, or lack thereof, in the object called its "thermal condition."
The most typical type of thermography camera resembles a typical camcorder and
produces a live television picture of heat radiation. More sophisticated cameras
can actually measure the temperatures of any object or surface in the image
and produce false color images that make interpretation of thermal patterns
easier. An image produced by an infrared camera is called a thermogram or sometimes
To understand IT as a tool it is necessary to understand how it works. Thermal
or infrared energy is light that is not visible to humans because its wavelength
is too long to be detected by the human eye. Thermal or infrared energy (IR)
is the part of the electromagnetic spectrum that we perceive as heat. Unlike
visible light, in the infrared world, everything with a temperature above absolute
zero emits heat. Even very cold objects, like ice cubes, emit infrared. The
higher the object's temperature, the greater the IR radiation emitted. Infrared
allows people to see what their eyes normally cannot see.
IT cameras produce images of invisible infrared or "heat" radiation. The
IT camera can provide precise noncontact temperature measurement capabilities.
The existence of moisture—a substance cooler than normal construction materials—can
be used to detect conditions that promote mold growth. Mold related problems
can be detected before the mold is visible to the eye or detectable by the nose.
IT cameras are extremely cost-effective, valuable diagnostic tools in construction
related problems of water intrusion and mold growth.
But finding a problem with an infrared camera is not a solution. It is the
start of an investigation that will help the property owner or developer stop
a problem before it becomes serious. An infrared camera image alone, without
accurate temperature measurements, says very little about the condition of a
structure or its susceptibility to mold growth. An infrared image without measurement
can be misleading because it may visually suggest a problem that does not exist.
Infrared cameras that incorporate temperature measurement allow professionals
to make well-informed judgments about the operating condition of a structure.
Temperature measurements can be compared with historical operating temperatures,
or with infrared readings of similar structures at the same time, to determine
if a significant temperature rise will compromise the structural integrity or
encourage mold growth.
Digital image storage, available on most FLIR2
Systems infrared cameras, produces calibrated thermal images that contain over
78,000 independent temperature measurements that can be measured at any time
with FLIR Systems infrared software products on standard PC platforms.
Used properly, a thermal imaging camera can provide valuable information
during moisture assessments, remediation oversight, energy audits, roof and
electrical system inspections and water damage investigations. Temperature difference
caused by evaporation, radiation, thermal bridging, infiltration/exfiltration,
and other sources must all be carefully evaluated. A thermal image, like the
image of a roof below, looks like an impressionist painting by an artist on
inspector trained to properly use the IR camera can read the information to
spot suspect areas that are not visible to the naked eye. The findings can later
be verified using electronic, data-logging moisture detection equipment and
in some cases core samples from the roofs or walls.
The inspector uses thermal imaging and data logging moisture detection equipment
to establish that the inspector assesses all areas of concern. The extra verification
gives additional assurance that the findings from the IR camera are defensible.
All property owners and their insurers faced with a claim alleging mold infestation
can find these tools essential to the decision process and proper maintenance
of the structure.
When suspect areas are found they can be visually documented using the IR
camera. Images, like those obtained from an IR Camera, are easier for a layperson
or nontechnical person to understand. Findings from the IR camera can be explained
to the property owner or the insurer's personnel combined with the verification
obtained by using data-logging moisture detection equipment with time stamp
and/or destructive testing.
The time saved using infrared, and the larger areas covered rapidly by an
IR Camera, can save time and money by providing a faster, more efficient and
more reliable survey. An IR camera can detect moisture located behind interior
walls under the right conditions. The temperature difference created by the
presence of moisture on the inside surface of a wall will appear differently
than the surrounding area. IR and IT experts recommend that property owners
or their insurers should use IR cameras and IT for moisture detection under
the following circumstances.
After any water damage event like a flood, broken water lines, equipment
failure, roof leaks, etc.
Before warranty expiration on new construction. (In
many cases, those damp basement walls are explained away as "during construction"
moisture. It pays to make sure before warranty expiration.)
Before acquiring real estate suspected of having hidden moisture damage.
(Don't believe the story about the house has
been vacant and closed up. Musty odors are caused by moisture.)
When basement walls are covered by finish materials, and the inspector
cannot give a definitive answer on moisture issues.
When suspected plumbing leaks have occurred from in-slab water supply
and/or waste lines.
When doors, windows, or other openings in the structure are suspected
When performing an energy audit of the building to determine areas of
infiltration and exfiltration.
To determine adequacy of insulation. Wet insulation is a poor insulator
but is a great conductor of heat.
Infrared inspection of the roof can determine potential for ice dams,
plugged drains, and water retention that may cause roof damage and/or leakage.
Locating hidden leakage and/or dampness under resilient flooring.
Locating wet areas in non-accessible crawlspaces.
Infrared technology is especially useful for inspecting flat roofing systems
and synthetic stucco systems, which rarely give any visual clues as to their
condition or the location of leaks and moisture retention. Litigation involving
synthetic stucco, or exterior insulating finish systems (EIFS), is rampant nationwide.
EIFS exterior cladding is blamed by many property owners for retaining moisture
behind. The property owners claim that EIFS, because it retains water behind
it, promotes mold growth and rotting within exterior wall cavities.
IR technology is being supplemented with a living tool: dogs trained to sniff
out the existence of mold. For example, Lab Results LLC,3
brought the first certified Mold Dog™, Oreo, to the Northeast and provides a
network of independent certified mold dog handlers ready to take on big jobs
when needed. While a mold-detection canine can quickly find mold inside a home
or commercial building, infrared thermal imaging has the edge on the exterior
and in detailing—with imagery, the location, and extent of mold infestation.
Properly used under the right conditions, infrared thermography can serve
as an early warning system for flat roofs that tend to retain water long before
they actively leak. The technology also can detect temperature variations that
an infrared thermographer would use to find moisture accumulation, condensation,
infiltration, and leakage in wall systems and windows, all of which can provide
an environment conducive to mold growth.
The combined use of Mold Dogs™ and infrared thermal imaging during EIFS inspections
can be one of the most effective nondestructive and non-invasive method of surveying
a property for potential mold and moisture problems. The combination can tell
a property owner or potential buyer whether there may be a serious hidden problem,
before any cutting or sampling is done.
Typical current inspection methods involve much guesswork and the random
cutting of core samples or pieces of walls—both inside and out—to analyze for
mold and moisture. A combined Mold Dog™ and infrared thermal imaging inspection
can protect a potential buyer from acquiring a lemon property or from incurring
repair and remediation costs far beyond a building's value.
A mold problem is a moisture problem, so when IR is used to find moisture,
and it actually finds moisture, it becomes possible to prevent mold and rot
from taking hold or to remove the mold that actually grows. Some examples of
IR Cameras that can be used for IT inspections of structures to avoid mold growth
follow. (The descriptions and photos were taken from the manufacturer's Web
site and are not intended to be an advertisement for or endorsement of any of
NEW—First Look Palm IR 500.The
latest and greatest thermal imaging camera from Raytheon. The new Palm IR 500
is the first radiometric camera from the company based on their exclusive BST
detector technology. Early reports indicate that the image is much improved
and temperature measurement should be accurate within range. The system looks
like a winner and the Compaq IPAQ is a nice bonus. This is a fantastic imager
for every application including predictive maintenance, energy audits, printed
circuit board scans, and more.
Palm IR PRO Specials.Packages
for the latest in thermal imaging performance. The IR PRO combines high resolution
imaging, comfortable LCD viewing, and Digital Compact Flash image storage. We
have special packages for Predictive Maintenance, Home Energy Audits, and Security/Surveillance
Palm IR 250 DIGITAL.The
venerable IR 250 has been much improved with its latest overhaul. "We have a
completely new product here and it kicks butt!" The New digital detector produces
a super crisp image and the variable digital zoom you have all been waiting
for is finally here. Convenience features like numeric on-screen gain and level
symbology and our newest value added packages make the IR-250 D an interesting
Palm IR 225.The
newest addition to the NightSight family is the IR-225 compact thermal imager.
This new unit shatters the $10k barrier to bring you quality Raytheon imaging
at the greatest possible value. This is one unit that you can truly afford to
implement on a widespread basis.
Similarly, FLIR ThermaCAM® E4 infrared camera features image post-processing,
plus alarming and multiple target spots in rugged 1.5 pound package. The Model
E4 introduced the use of a radiometric JPEG (Joint Photographic Experts Group)
image format that allows image post-processing on the camera or on a PC. As
a result, the E4 also provides three independent, movable spot temperature cursors,
and audible "beep" alarming for high, low, or temperature-difference thresholds.
The radiometric JPEG file format integrates thermographic functionality with
the familiar, world-standard JPEG file format used in Web and other graphics
environments. The E4 can store images as radiometric JPEG files, which retain
full thermographic functionality. It can also store images as nonradiometric
JPEG files. Both radiometric and nonradiometric JPEG formats can be readily
inserted into standard word processing and desktop publishing applications.4
An IR camera can look at a wall after a fire and show where water has accumulated
that would be invisible to the human eye. A modern advanced IR camera is literally
a handheld personal computer that measures temperature with an advanced focal
plane array detector. The most powerful cameras provide 12-bit recording, enabling
users to view and measure a scene that contains very hot and very cold temperatures
without losing the ability to measure thermal variations of less than 0.1 deg
Camera options, such as bar code readers for image tracking, have extended
the functionality of IR imaging systems to match the needs of computerized maintenance
management systems (CMMS). Bar code tracking offers accurate, operator-independent
data entry that adds pertinent condition comments directly to the stored IR
image. Even where bar codes are not used to identify equipment, the bar code
standardizes all inspection comments associated with the image.
At the completion of an inspection task, stored images are usually transferred
to either a stand-alone thermal analysis or reporting software package, or to
the main CMMS. Regardless of the type of maintenance management system at a
facility, the primary task at this point is to archive collected data and generate
work orders for corrective actions. When required, a full range of image analysis
software features allow the user to extract temperature values from the stored
images on any PC with the Windows operating system.
IR system suppliers are delivering real-time IR workstations that can measure
dynamic temperature changes in equipment and processes. The call for more sophisticated
application of IR imaging is often initiated after production and engineering
departments have battled quality or efficiency problems in the construction
of structures that encourage mold growth. The problems may range from poor adhesion
of hot-set glues to quality variations in plastic films, from poor uniformity
in glass products to roofing materials that are not water-tight; from windows
that leak to water wicking up through concrete slabs.
It is not uncommon that as management pushes for increased quality that effective
methods of testing quality and avoidance of water intrusion are needed by everyone
in the business of owning or building structures. In these production situations,
the new real-time IR thermal imaging systems are most useful. The systems consist
of two primary components:
A portable Pentium PC with a digital recording system and software integrated
to acquire real-time digital video and to display it in color, extract temperature
information, and record the real-time sequences for extended analysis, and
A handheld, high-resolution FPA camera.
A key feature is the digital video interface, which transmits every temperature
measurement pixel generated by the camera. The camera also can be disconnected
from the system and used in traditional snapshot mode. What makes these workstations
so useful for troubleshooting construction problems is their ability to acquire,
store, and analyze sequences of real-time IR images of the structure under investigation
or during construction. The system analyzes, displays, and stores up to 60 calibrated
IR images every second. The systems use off-the-shelf components to make upgrades
possible and ensure compatibility with traditional software.
A relatively slow and inexpensive 200 MHz Pentium PC with its high-speed
PCI bus makes an excellent platform for thermal imaging. A digital frame grabber
accepts the digital video transmitted by the camera and transfers it to the
high-bandwidth PCI bus. High-capacity hard disk subsystems designed for multimedia
applications store the data for subsequent review and further analysis.
Software analysis tools give the system a VCR-like user interface for controlling
the digital video recording and playback. Users first position the camera and
adjust the viewing temperature range and then select the rate and length for
which images are stored to the internal drive, ranging from 60 Hz for as long
as 20 minutes, or as slow as one image every hour for weeks. Storage of the
video can be initiated from the keyboard or a signal from the device under observation.
Once data have been recorded, viewing controls (such as play, fast forward,
rewind, slow motion, and time lapse) can be used to review the process, equipment,
or event under study.
The software provides a full range of tools for extracting temperature data
from the collected thermal image sequence. They range from simple points, areas,
and lines to complex regions that help the user measure only specific components
of interest. If live sequences reveal dynamic trends, a tool automatically extracts
data from a sequence of images and generates a graph for review. Captured data
can be exported to other systems so maintenance managers can integrate all maintenance
test data into a CMMS.5
1For some detail, see "Answers
to the Common Questions People Ask about Infrared Thermography."
Systems is a leading manufacturer of innovative imaging systems that include
infrared cameras, aerial broadcast cameras, and machine vision systems. The
company has been supplying thermography and night vision equipment to science,
industry, law enforcement and the military for over 30 years.
Results LLC Pioneers Use of Infrared Thermography With Mold Dogs(TM) in Mold
& Moisture Detection."
4For more information, see "Infrared
Camera Measures 3 Spot Temperatures on Image."
5For details, see "Infrared
Options Multiply for Condition Monitoring."
© Barry Zalma 2004
Opinions expressed in Expert Commentary articles are those of the author and are
not necessarily held by the author's employer or IRMI. Expert Commentary articles
and other IRMI Online content do not purport to provide legal, accounting, or other
professional advice or opinion. If such advice is needed, consult with your attorney,
accountant, or other qualified adviser.
Please use the print button on the IRMI toolbar to print/preview this page.
© 2000-2015 International Risk Management Institute, Inc. (IRMI). All rights reserved.