The Infrared Consultants Blog

ERMI - The beginning of a new environmental diagnostic era? by: Steven Parkhurst

Viable Bioaerosol Sampling 

Remember when the only tools we carried for detecting mold were Q-tip swabs, malt agar plates, scotch tape, an N6 sampling train and a rabbit’s foot?  Well, at least the well-equipped investigator carried these items about a decade ago.  Collecting viable bioaerosol samples was and is truly an art form.  First you had to select the appropriate agar media or plan to take multiple air samples to ensure you didn’t overlook any species of environmental molds.  You had to check their expiration date and make sure they’re still current.  Next, you had to calibrate your high volume pump to 28.3 liters per minute with your Andersen N6 sampler in place.  This was a tricky part…I saw more Rube Goldberg contraptions devised to try to do this including using Folger’s coffee cans coupled with test tube plugs and Tygon tubing.  After calibration, your N6 sampler and hands were sanitized with alcohol-based handiwipes.  Next you uncovered your agar plate just seconds before placing it on the lower stage of the N6 base trying hard not to breathe on it or let it get close to your body in fear of cross-contamination. 

Visually you checked the agar for any imperfections and fungal growth disposing of anything that appeared questionable.  For reasons unknown, the agar plate positioning tabs on the N6 base never quite lined up with the Petri dish’s plastic circumference so it took a few moments to ensure the agar plate seated correctly.  After placing the aluminum cone and 400 jet hole classification stage in place, you positioned the three spring-loaded prongs to hold the unit together.  Now if you held your tongue just right, you were able to get the top part to seal to the bottom part otherwise leakage would occur.  After running the sampler for 3-5 minutes, you removed the prongs lifting the top section off only to discover there were air dimples only on half the plate.  Arrgh!!  Your sampler leaked.  Time to dispose of the sample and start over again with a new agar plate.  The second time you got it right so you sealed the Petri dish with stretchable wax or black electrical tape and placed it in a ziplock bag.  Once all your samples were collected, a small playmate cooler was opened and a block of blue ice was placed inside along with your samples.  But don’t ship these babies on Friday or Saturday because they may sit in a hot warehouse or drop-off box for a day or two. 

This was and remains the state-of-the-art preferred sampling method for bioaerosols for decades.  But as usual, there was little in the form of data interpretation guidelines.  Then from 1986-1989, the American Conference of Governmental Industrial Hygienists (ACGIH) developed a Threshold Limit Value (TLV) for viable mold bioaerosols of 1,000 colony forming units (CFU/m3).  Finally, an authoritative guideline by which we could live and breathe by.  But this guideline had the half-life of Radon222’s alpha decay into Polonium218 – very short.  It was quickly rescinded leaving field practitioners in search of another device by which to interpret our painstakingly collected viable bioaerosol data. 

The ACGIH redeemed themselves by publishing the “Bioaerosols: Assessment and Control” reference in 1999.  This book has become the authoritative guide for understanding the behavior of bioaerosols and interpreting their data.  The ACGIH maintains that viable fungal data should compare inside versus outside concentrations – normally exterior levels are higher than interior, comparisons of the species compositions indoors and out, and the presence of indicator species in the indoor environment.1  Of course, the ACGIH provided the regretful disclaimer that, 

“Although, ACGIH has previously published numerical guidelines, at the time of this publication, ACGIH does not support any existing numerical criteria for interpreting data on biological agents from source or air samples in non-manufacturing environments.”1 

In 2000, the Indoor Air Quality Association (IAQA) bravely stepped forward when they published their IAQA 01-2000 “Recommended Guidelines for Indoor Environments” based on research published by Dr. L. Robinson in 1997.  Their recommended guideline for culturable fungal bioaerosols is a maximum of 300 CFU/m3 total; 50 CFU/m3 for individual species (excepting Cladosporium).2  Until then, we were left with only the guiding words of the ACGIH which recommended, “…gathering the best data possible and using knowledge, experience, expert opinion, logic and common sense to interpret information and design control and remediation strategies.”1  While relatively innocuous and albeit, well written, this statement left room for a wide range of data interpretations leaving each investigator to be his own New Age-like divine mold guru.  Having been summoned as an expert on many occasions, I find it fascinating the diversity of opinions offered given the same set of sampling data.  These endogenous ambiguities persist within the data interpretive process today. 

Spore Traps 

In the mid-1990s, spore traps became the sampling method de jour for collecting bioaerosols.  Quick turn arounds, low cost, multiple genera identification, easy shipping and identification of allergens became the selling points that convinced investigators to switch from culturable sampling to non-viable sampling.  However, the downside of spore traps was often equally vexing given their wide variability, indistinct determination of Aspergillus/Penicillium genera spores, difficulty attaining a valid control (snow, rain, temperature), and no interpretive guidelines.  In the black-whole void of non-viable interpretive guidelines, investigators simply adopted the ACGIH’s approach toward interpreting culturable fungal data even though this was clearly not intended by the ACGIH authors.  They explain, 

“Comparisons of the species compositions of indoor and outdoor populations requires accurate identification of fungal species not simply identification to the genus level.”1 

Spore traps only identify to the genus level.  Nevertheless, we continued down the tortuous, unknown path of non-viable data collection primarily because there was no better way and no government regulatory direction to do otherwise.  So as the McGyver’s that we are, we adapted and learned, and through a series of trial-and-error field experiments we’ve become comfortable using spore traps and tape lifts for the bulk of our residential and commercial fungal investigations. 

More importantly, in a recent study published in Science of the Total Environment, April 2007, the authors collected bioaerosol samples using DNA analysis (MSQPCR) to attain speciation of air samples for comparison between inside and outside species and concentrations.  Air samples were collected over a 48-hour (yes, a 2-day) sampling period….significantly longer than our traditional 5-10 minute bioaerosol samples.  The authors found that total spore concentrations between indoor and outdoor levels were significantly different, with inside levels lower than outside levels (which is good…that’s what we’d expect).  HOWEVER, there was no correlation in the 36 mold species concentrations [except Aspergillus penicillioides, Cladosporium cladosporiodes (I & II) and Cladosporium herbarium].  In other words, for most mold species (the other 33 measured), there was no rhyme or reason, that is; no correlation between inside and outside concentrations.  According to the authors, the significance of their findings was, “…that evaluating the mold burden indoors by a simple genus level comparison to the outdoors may be misleading.”3   

Other studies have developed similar findings.  For example, Spicer and Gangloff (2005) showed that “the levels of fungi in the outdoor air varied significantly between morning and afternoon …with no pattern by species, time of day or location.”4 What all this means is that collecting an outside sample when using spore trap sampling and analysis is VIRTUALLY WORTHLESS!!!  Comparing inside to outside spore concentrations at the genera level is a senseless and meaningless academic exercise. 

Until Now…ERMI 

In 2006, HUD carried-out the American Healthy Home Survey of a statistically representative sample of approximately 1100 homes across the US and analyzed the dust with the ERMI analysis.  For each sample, the mold concentration of each species (spores/mg of dust) is converted to its algebraic log then summed for the respective groups.  The sum of logs of Group 2 molds is subtracted from the sum of logs of Group 1 molds to arrive at an ERMI score.  This log transformation adjusts for magnitudinal variance in spore concentrations associated with region (Florida vs. Arizona) and season (winter vs. summer).  The subtraction of Group 2 mold from Group 1 mold normalizes the data to account for variation in cleaning habits and growth substrate (building materials).   The 1100 values for the homes were assembled from lowest to highest to create the ERMI scale from -10 to 20 or even higher (Figure 1).  These homes were then divided into four quartiles (25% lowest, 25% highest etc.) based on the percentage of homes in each (Figure 1).  Now any home sampled and analyzed in the same way can be placed on the ERMI index, to determine its relative moldiness compared to the U.S.5 

ERMI historic bulk samples are analyzed using Mold Specific Quantitative Polymerase Chain Reaction or DNA sequencing.   MSQPCR is a highly accurate and sensitive molecular technique for the detection and quantification of molds with indisputable 99.99% accuracy.  It is objective and specific because it is a detection system based on unique DNA sequences.6 

With ERMI, no more comparing inside to outside spore concentrations, no more wondering what does A/P-like really mean, no more overloads, no more aborted studies due to inclement weather conditions and open windows, far more clarity regarding whether a home is mold impacted, and far more accurate, targeted and comprehensive analyses.  So not only can it be used on initial mold investigations but also on post-remediation verification studies, wall cavity checks, on property damage water-impact claims, on property transfers, and potentially on personal injury suits. 

Admittedly, though, ERMI does have a gray area, or actually the yellow zone.  It’s the middle quartiles between the low and high quartiles.  In this area, homes may have the presence of water impact molds at lower concentrations indicating some water-impact mold contamination exists.  What to do with these results will depend on the observational powers of the inspector, the species of molds present, and the health status of the occupants.  I call it the Contingency Zone…because whatever actions or decisions that are made are contingent on factors other than the environmental data.  Clearly the actions in the Green and Red zones are predictable and obvious, whereas those homes found in the middle of the chart require more thoughtful consideration of the building and its occupants. 

Equilibrium Theory of Indoor Spore Dispersion 

Homes and businesses receiving a high ERMI score (≥5) are more likely to have unwanted indoor mold growth than those homes that receive a lower ERMI score.  A high score is indicative of a current or past water intrusion event, such a s a broken pipe or window that leaks every time it rains.  Often mold won’t be visible but hidden in wall cavities, crawlspaces or attics.  However, as mold grows, it releases small microscopic spores, usually between 1-5 micrometers in diameter.  These spores become airborne and move from either dormant or growing, but highly concentrated spore beds, into living spaces.  For example, mold growing on the interior of a wall cavity serves as a common spore bed, which may contain millions if not billions of spores. 

Since mold spores are small, they can easily move through porous construction materials, outlets, and various wall apertures.  Spores are dislodged and moved by updrafts, downdrafts, air infiltration, vibrations (such as a garage door opening) and may follow extremely circuitous paths to end up in the living space.  Once in the living space, spores settle of the air and are deposited in various dust reservoirs.  Eventually, over several weeks, spore concentrations reach equilibrium between the interior building space and living space.  Once equilibrium is reached, invasive wall cavity sampling is unnecessary because a portion of the water-impact spores (Group 1) in the wall cavity now occupies dust reservoirs in the living space.  Hence, a representative dust sample from the living space is all that is required to determine the EPA ERMI score, which identifies and quantifies the Group 1 and 2 molds that are present.  ERMI analysis in part replaces multiple destructive sampling methods such as wall cavity checks or bulk drywall removal with a single non-invasive dust sample.7 

Is ERMI Related to Health Concerns? 

Now with this new highly accurate scientific tool there is emerging linkages between moldy environments and respiratory problems.  Research by Dr. Vesper and others has been able to link homes with Group 1 molds to the likely development of asthma in children living in water-damaged homes.  A relative moldiness index (RMI) as seen in ERMI was able to make this prediction.  In this study bulk dust samples were taken from 82 homes, 60 where an asthmatic child lived and 22 controls.  Samples were analyzed using MSQPCR with molds categorized into Group 1 and Group 2.  The mean age of the asthmatic children was 6.8 years and the majority was black (66%).  Over 75% of the children had mild persistent to severe persistent asthma.  Among the water-damaged homes where asthma was present, the following molds were measured at higher levels than in control homes:  Scopulariopis brevicaulis, Trichoderma viride, Penicillium crustosum, Stachybotrys chartarum and Wallemia sebi. 

They concluded that, “The ERMI values may be a useful tool for predicting the mold condition of a home.  If Group 1 molds are discovered, water-damage remediation and mold removal might be considered as part of the total prevention plan in an asthmatic child’s home.”8  This relatively modest assertion has far greater implications than what was initially reported. 

Its significance centers on its ability to predict the likely development of asthma in children living in water-damaged homes.  While it has been known for years that environmental molds are related to allergies and asthma, the ability to assign some level of causation and predict its outcome has been elusive and ethereal for most serious investigators and researchers.  While ERMI is not a bright line between good health and disease, it is emerging as the best tool investigators can use when linking fungal exposures to respiratory illnesses, in particular childhood asthma.  Many mold-related illnesses remain idiopathic and highly dependent on the individual’s immune system -- either its hypersensitivity or suppression.  Nevertheless, we are getting closer to understanding what molds and environmental conditions lend themselves to mold pathologies.  ERMI has taken us one giant step closer to understanding this complex relationship between humans, our environment, and the microorganisms found therein.   

References 

1)         “Bioaerosols:  Assessment and Control”, ACGIH, 1999; Sections 7.3-7.4, pp. 7-5,-6. 

2)         “Recommended Guidelines for Indoor Environments”, Indoor Air Quality Association, Inc., IAQA 01-2000; Section 8.0, p. 6. 

3)         Meklin T, et. al., Comparison of mold concentrations quantified by MSQPCR in indoor and outdoor air sampled simultaneously, Science of the Total Environment, 382 (2007):130-134. 

4)         Spicer R, Gangloff H. Establishing site specific reference levels for fungi in outdoor air for building evaluation. J Occup Environ Hyg 2005; 2:257-66. 

5)         Vesper SJ, McKinstry, C., Haugland RA, Wymer L, Ashley P, Cox D, DeWalt G, Friedman W. Development of an Environmental Relative Moldiness Indexsm for homes in the U.S.  Journal of Occupational and Environmental Medicine. In Press. 2007  

6)         Vesper, M, S. Vesper, et. al.; “Mold-Specific Quantitative PCR:  The Emerging Standard in Mold Analysis”, American Laboratory, January 2005, p.10. 

7)         Sobek, E, The EPA ERMI Analysis, White Paper; Clean Air Laboratories, April 2007. 

8)         Vesper, S., et. al., “Specific Molds Associated With Asthma in Water-Damaged Homes”, Journal of Environmental Monitoring, Vol. 48, No. 8, August 2006: 853-858.



Discovering Hidden Water Intrusion Through Infrared and DNA by: Irv Kraut

A combination of two emerging technologies (Infrared Thermography & DNA analysis) is allowing investigators the ability to discover, identify and resolve concerns specific to historic water intrusion and the damages that has or may occur.  

Often insurance claims following a storm event or plumbing leak are difficult to quantify as water may have wicked or traveled from its original entry point. In other words  if water has entered a property through a second floor exterior French door it may have penetrated to the room below and run a metal chase to other areas of the property. The presence of water in these other areas are often hidden from view and only become visible when delimitation has occurred and or a musty odor becomes noticeable. 

The use of Infrared enables the investigator the ability to see temperature anomalies associated with water in all areas of the property in real time and can track or water map the movement of moisture from its inception to its end point. Infrared also provides photographic documentation for inclusion in subsequent written reports. 

DNA is a new technology that enables the investigator the ability to test various rooms within the property to determine if water impact fungi have developed. The presence or lack thereof of indicator fungi discovered by testing the DNA of vacuumed dust will support Infrared results. Water impact fungi are latent microbial fingerprints of a water event and when combined with Infrared make a compelling science based conclusion of the presence of moisture in a given area possible.



Structural Integrity: Identifying Cell Fills with IR

The use of infrared thermography as a quality assurance standard for the presence or absence of grouted cell fills is becoming more common in the world of concrete masonry building. Masonry is one commonly used building materials. This is due to it being such a robust, versatile, and cost effective material.  The traditional method of testing for properly filled CMU grout cell fills was to simply walk around with a hammer and tap on the walls in the areas where the fills were suppose to be.  This is a very time consuming method, and unless the entire wall is tapped from ground to tie beam any voids in the fill may go undetected. Wtih infrared thermography, an image is produced and the cell fills, or lack there of, are cleary visible.  For more information on the detection of cell fills check out www.infraredconsultants.com/cell-fill-tie-beam-evaluations.html.


Vibration Analysis by: Paul Ogletree

Vibration is simply the movement of a machine or machine part back and forth from its position of rest. One of the earliest signs of a machine failure is the propagation of vibration. Vibration Analysis can be performed on all moving parts and rotating equipment in any facility. Each rotating machine has its own vibration signature as a result of the rotation of bearings, shafts and gears. Vibration analysis can detect problems caused by bearing damage, shaft imbalance, bent shafts, bad drive belts, and looseness. Early detection using vibration analysis prevents costly unscheduled shutdowns which also can provide sufficient time to schedule maintenance and order new parts prior to shutdown.       

 

Vibration Analysis is an effective way of increasing reliability of all your equipment and improve maintenance management in your facility. When implemented, it can identify machine faults, simplify repairs, and pinpoint problems before being noticed by facility maintenance personnel. This can eliminate or lessen downtime and extend the life of equipment. Vibration analysis also could yield a possible energy savings of up to 15%. This savings is directly related to misalignment and imbalance of rotating equipment.

                                    

Catastrophic machine failures can also have a chain reaction on the associated rotating equipment. These failures can cost as much as ten times more to repair than machinery that was identified prior to failure. The maintenance costs to repair failures can include overtime maintenance labor, labor cost of idle production personnel, and no product output while repairs are made. This can be eliminated by implementing a proactive predictive maintenance program. This in turn, will lead to company profits not previously achieved because of the “run to failure” mentality.

 

IRC uses the very latest in vibration analysis equipment by Commtest, the industry leader in analysis equipment. Visit their site at http://www.commtest.com/ to see “The Revolution” in vibration analysis.



Ultrasonic

Ultrasonic leak detection is an instant way for major oil companies to locate hydrocarbon gas leaks. Due to its effectiveness, it is a widely used alternative to traditional fixed gas detector systems. This is due to the fact that most problems are only audibly detectable in the ultrasonic range.

This use of ultrasonic leak detection for the detection of the source of escaping water from pipes beneath concrete slabs works from the same principles.  Problems are first detectable in the ultrasonic range and early detection can prevent catastrophic, costly damages. By combining infrared thermography and ultrasonic, we are able to pinpoint water leaks at their source. The use of Infrared locates the area of moisture and then ultrasonic listens for the exact point of escape. This allows minimal destruction, in terms of area, to the concrete slab to alleviate the leak.



Introduction of Quality Assurance Program

Infrared Consultants is proud to introduce its Quality Assurance Program (QAP) to builders.  The QAP program is designed as a third party inspection program to assist builders and potential home buyers in preventing potential moisture intrusions and prevent costly future repairs and mold remediations.  The program focuses on the critical areas of potential moisture intrusion around the buildings exterior perimeter during construction.The QAP is designed to oversee the project in phased inspections.  With several site visits involved in the QAP we are able to detect any defects at the different stages of construction so that these defects can be corrected before they become a problem.The combination of our QAP and the newly developed standard reference index for indoor air quality will give builders and homeowners alike complete peace of mind! ERMI (Environment Relative Moldiness Index) is the new standard developed by the US EPA to score the moldiness of a home or structure.  Upon the completion of the pre-closing inspection of the QAP the home will receive a certificate of compliance with an ERMI score showing the home has successfully completed the series of construction processes and has passed the environmental inspection.

OUR PROACTIVE APPROACH WILL SAVE YOU MONEY!



DNA Forensic Mold Detection by Dr. Edward Sobek

DNA FORENSIC MOLD DETECTION©By: Edward A. Sobek, Ph.D. 

Extensive research conducted by the US EPA, using State-of-the-Art DNA forensics, has established the Environmental Relative Moldiness Index, otherwise known by the acronym ERMI.  The ERMI study narrowed down the total number of critical mold species to 36 indoor-indicator mold species.  Furthermore, the 36 species were subdivided into two very different groups of mold (fungal) species; these included the Group 1 and Group 2 molds.  The Group 2 molds were found to be common in most homes and in low concentrations.  Occupants living and working in indoor environments that contained predominantly Group 2 molds were healthy and suffered few respiratory related illnesses, nor did the building structures suffer leaks and water intrusion.  However, Group 1 molds were much less benign, and occupants of these homes and environments suffered significant respiratory and asthma related illnesses.  Moreover, Group 1 molds were significantly correlated to water intrusion due to poor construction or leaking pipes.  Furthermore, EPA scientist and other reputable scientific investigators have amassed a body of published scientific research that conveys a major paradigm shift in the way mold samples are both collected and analyzed. 

 

Currently 99% of all mold samples are collected from the air.  Inspectors pump air, often for as little as 5 minutes, onto a sticky device called a spore-trap (not unlike flypaper).    They send the spore trap to a lab for analysis, and the lab spits back a report, based on the shape and size of the spores they see. It is important to keep in mind, that a mold cannot be identified as belonging to a particular species using a spore trap analysis, regardless of how much training or how many degrees a spore trap analyst has.  Unfortunately, many of the group 1 and group 2 mold spores are small and round and all get lumped into a common small-round spore trap grouping called Asp/Pen.  Hence, neither an ERMI score nor any substantial conclusion can be drawn from spore trap analysis.

 

The EPA solved this problem by using good science to make major breakthroughs in both mold sampling and analysis.  First, the EPA identified the best technology, to date, to identify mold.  That technology is called quantitative PCR or qPCR for short.  Quantitative PCR is used in many fields of science, such as genetics and cancer research.  The qPCR technology directly probes the DNA of mold with 99.9% accuracy to detect which species of mold are present and how many spores of each species are contaminating the indoor environment.  Secondly, the EPA used qPCR to probe the DNA of molds from the various reservoirs in homes.  Surprisingly, they found air to be a poor correlate for detecting group 1 mold contamination (the water intrusion/asthma molds).  So they looked elsewhere, and found that every indoor environment harbors a stable mold reservoir; that reservoir was dust.  Moreover, the dust held an historical account of indoor mold.  Hence, indoor dust has a historical moldy tale to tell, which is read from mold DNA.  Sometimes that tale is the sorrowful account of leaky roofs, windows or pipes (the DNA identifies many group 1 mold species), other times it is a story of a happy dry home (common group 2 mold species).  All buildings have dust and by analyzing the DNA in that dust for mold, all skeletons come out of the closet.  And those skeletons, whether good or bad, are reflected in the EPA’s ERMI index.  The ERMI index is just a score based on the amounts of group 1 (water intrusion) versus group 2 molds (common).  The ERMI score from DNA analysis of dust lets a building or home owner know whether their home has group 2 molds and is similar to the rest of the healthy homes identified in the EPA studies, or if it is infested by group 1 mold species, where water intrusion and respiratory problems are common.    

 Published Scientific Literature 

Mannino DM, Homa DM, Akinbami LJ, et al. Surveillance for asthma-United States, 1980-1999. MMWR Morb Mortal Wkly Rep. 2002;51:1-13.

Williamson IJ, Martin CJ, McGill G, et al. Damp housing and asthma: a case-control study. Thorax. 1997;52:229-234.

Belanger K, Beckett W, Triche E, et al. Symptoms of wheeze and persistent cough in the first year of life: associations with indoor allergens, air contaminants and maternal history of asthma. Am J Epidemiol. 2003;158:195-202.

Dales RE, Miller, D. Residential fungal contamination and health: microbial cohabitants as covariates. Environ Health Perspect. 1999;107:481-483.

Institute of Medicine, National Academies of Science. Damp Indoor Spaces and Health. The National Academies Press; 2004:355.

Vesper SJ, Varma M, Wymer LJ, et al. Quantitative polymerase chain reaction analysis of fungi in dust from homes of infants who developed idiopathic pulmonary hemorrhaging. J Occup Environ Med. 2004;46:596-601.

Dearborn DG, Kercsmar CW, Schluctler MD, et al. Home interventions regarding mold and moisture and the impact on the respiratory health of children. Annual Meeting Inter Soc Exposure Assessment; Philadelphia; October 2004.

Haugland RA, Brinkman NE, Vesper SJ. Evaluation of rapid DNA extraction methods for the quantitative detection of fungal cells using real time PCR analysis. J Microbiol Methods. 2002;50:319-323.

Brinkman NE, Haugland RA, Wymer LJ, et al. Evaluation of a rapid, quantitative real-time PCR method for cellular enumeration of pathogenic Candida species in water. Appl Environ Microbiol. 2003;69:1775-1782.

Haugland RA, Varma M, Wymer LJ, et al. Quantitative PCR of selected Aspergillus, Penicillium and Paecilomyces species. Syst Appl Microbiol. 2004;27:198-210.

Helsel DR. Nondetects and Data Analysis, Statistics for Censored Environmental Data. Hoboken, NJ: Wiley and Sons Inc; 2005.

Meklin T, Haugland RA, Reponen T, et al. Quantitative PCR analysis of house dust can reveal abnormal mold conditions. J Environ Monit. 2004;6:615-620.

O'Connor GT, Walter M, Mitchell H, et al. Airborne fungi in the homes of children with asthma in low-income urban communities: the Inner-City Asthma Study. J Allergy Clin Immunol. 2004;114:599-606.

Nevalainene A, Seuri M. Of microbes and men. Indoor Air. 2005;9:58-64.

Kurup VP, Fink JN. Fungal allergen. In: Murphy JW, Friedman H, Bendinelli M, eds. New York: Plenum Press; 1993:393-404.

Chung Y, Coates NH, Viana ME, et al. Dose-dependent allergic responses to an extract of Penicillium chrysogenum in BALB/c mice. Toxicology. 2005;209:77-89.

Gergen PJ, Mortimer KM, Eggleston PA, et al. Results of the National Cooperative Inner City Asthma Study (NCICAS) environmental intervention to reduce cockroach allergen exposure in inner city homes. J Allergy Clin Immunol. 1999;103:501-506.

Flannigan B, Miller JD. Microbial growth in indoor environments. In: Flannigan B, Samson RA, Miller JD, eds. Microorganisms in Home and Indoor Work Environments. London: Taylor and Francis; 2001:35-67.



Thermography 101

Basic Thermography 101
Infrared Thermography is the technique that uses an infrared imaging and measurement camera to "see" and "measure" invisible infrared energy being emitted from an object.Thermal, or infrared energy, is energy is not visible because its wavelength is too long for the sensors in our eyes to detect. It is the part of the electromagnetic spectrum that we perceive as heat. Unlike visible light, in the infrared spectrum, everything with a temperature above absolute zero emits infrared electromagnetic energy. Even cold objects such as ice cubes, emit infrared radiation. The higher the temperature of the object, the greater the infrared radiation emitted. The Infrared camera allows us to see what our eyes cannot!

In the industrial/commercial environment, almost everything gets hotter or cooler before it fails, making infrared cameras extremely valuable diagnostic tools with many diverse applications. And as industry strives to improve manufacturing efficiencies, manage energy, improve product quality, and enhance worker safety, new applications for infrared cameras continually emerge.

How Does the Camera “See” Heat?
All objects, cold or hot, radiate heat in the form of infrared energy. As an object increases in temperature, it radiates more energy, and the wavelength gets shorter. Infrared radiation, visible light and ultraviolet light are all forms of energy in the electromagnetic spectrum. The only difference is their wavelength or frequency.The human eye can only see a narrow range of wavelength in the electromagnetic spectrum. These wavelengths range in length from 0.4 to 0.7 microns, a micron is one millionth of a meter. Most of what the eye sees is reflections from objects that high energy from the sun or an incandescent light bulb is striking. If the temperature an object gets hot enough however, above 525°C the energy from that object will radiate energy in the visible spectrum and we will see it. This is when we see an object like the burner on an electric stove “glowing” red. In fact any time an object will emit or reflect energy in the same frequency of our eyes we will see it. Mostly, however we see reflections!

The infrared camera can detect infrared energy well before we can see it with our eyes. Most cameras can image temperatures from -20 to 500°C, and can be extended down to -40°C, and up to 2000°C. The camera converts this invisible infrared energy into a two-dimensional visual image and displays this on a standard TV monitor. Most industrial cameras can also make temperature measurements, with accuracies to around ±2% at 30°C. The thermal information is stored onto a disc and is later downloaded into a computer to create report.

Infrared Inspections are Simple!
However, taking thermal images and gathering thermal information is quite easy these days, just push the auto button and there is an image! This is simple on the surface, but it is not as easy as it sounds. The real work — and value — is what the thermographer understands about the object of interest, how it operates, the heat transfer within and to the surface of the object, how to adjust the camera to enhance the thermal details necessary to evaluate the image once it is stored and downloaded onto the computer. Then prepare a report that is accurate, clearly presented and is easy to read by the maintenance personnel, who generally do not know anything about infrared Thermography. As in any method of nondestructive testing, the interpretation of the information gathered takes both education and experience.



Infrared Thermography and DNA connect

Infrared Consultants and Clean Air Inspections has teamed up and developed a new technique that provides irrefutable evidence for water impact investigations.  Through the use of advanced thermal imaging techniques and DNA laboratory analysis they can identify historical water loss data by identifying the DNA fingerprints of "signature" water infiltration molds. Identifying signature water impact molds with DNA testing proves historical water intrusion has occurred and infrared themography can identify if the water intrusion is still active.


2007 International Builders Show

From February 7-10 Infrared Consultants attended the 2007 International Builders Show in Orlando, FL.  The shows attendance was estimated to be over 100,000 people. Infrared Consultants had several hundred viewers drop by their booth.  Viewers ranged from real estate agents, to builders, and architects and engineers. Most builders were interested in the ASTM water testing service and the moisture-free certification. Most architects and engineers were interested in the preventative maintenance program and litigation support.
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