159
TURNING CONTAINMENTS INSIDE OUT: A NEW LOOK AT CONTAINMENT DESIGN IN FUNGAL
REMEDIATION.
L. Rogers, S. Donham, Clayton Group Services, Tampa, FL.
Typically, negative pressure enclosures are constructed of critical barriers with air filtration devices exhausting air to depressurize the interior of the enclosure. In most instances, this design will satisfy the ultimate objective, that is, to prevent particulate and contaminants from migrating outside of the containment. Adhering to this strict definition of containments can be a costly endeavor for some projects where unusual circumstances prevail, such as removal from building exteriors, vertical shafts, or plenums. These are instances when this standard design doesn’t meet the needs or cannot be achieved. This presentation will explore different containment designs, such as positive pressure containments, secondary containment, and other designs to achieve the same goal in a more cost-effective manner. Case studies with demonstration data will be presented.
160
MOLD AND WATER DAMAGE INSPECTION USING INFRARED THERMOGRAPHY.
B. Weber, Four Star Cleaning and Restoration, Fremont, CA.
Introduction. Four Star Cleaning & Restoration used a FLIR infrared camera successfully to find the extent of the water damage caused by a chronic leak in an eight-year-old, two-story home and to enable us to accurately plan and estimate the cost of repairs. Discussion. A FLIR ThermaCAM® E4 infrared camera provided thermal images that immediately revealed an approximate 6°C temperature difference between wet (cold due to evaporative cooling) and dry (warmer) building components. Visual images were also taken to verify damaged areas and to track the moisture to its source.
Just below the cold air return grille in the living room, water staining was apparent with the naked eye. The IR camera revealed that the wet area was far more extensive—from the 18-foot ceiling, down to the grille, around the entry and living room alcove, and in the floor covering and wallboard of the family room. In addition, water gathered dangerously around a light switch.
An Indoor Environmental Professional established a protocol requiring that all materials containing visible fungal growth were to be removed and containment constructed to prohibit the spread of bioaerosols during demolition. After removal, a specialized cleaning including HEPA sanding, wire brushing, and initial HEPA vacuuming was scheduled, followed by a second HEPA vacuuming, wet wiping, tack wiping, final air scrubbing, and a final post-remediation inspection were to be performed. After these steps were completed, the water intrusion was traced to a roof valley flashing not installed properly. Reconstruction was completed, and the home should not leak again. Conclusion. The camera accurately enabled optimal resolution of the moisture problem and the remediation protocol precluded disrupting or relocating the occupant. The remediation was accomplished quickly and professionally, complete with photo documentation.
161
DETECTING MOISTURE ANOMALIES IN BUILDING ENVELOPES USING INFRARED THERMOGRAPHY:
A CASE STUDY.
J. Kominsky, Environmental Quality Management Inc., Cincinnati, OH; J. Luckino, Archatas Inc., Worthington, OH.
The problem of moisture in building envelopes may best be described as an elusive phenomenon in a heterogeneous medium. Visual examination is a reliable means of moisture detection in building walls after serious damage has been done. Traditional spot measurement instruments (conductance- and capacitance-types) are not ideally suited to cope with a wet anomaly that can change its shape, location, and content as conditions dictate. Infrared thermal imaging is a more versatile tool for in-situ moisture detection because it can be used to rapidly scan a surface to determine if moisture is present and detect a moisture problem in the formative stages, before it becomes serious.
This investigation involved a newly-constructed health care facility. It was prompted by owner concerns of potential areas of moisture intrusion through the envelope and resultant microbial colonization in the interstitial wall space. Infrared thermography was used to identify areas of probable moisture anomalies in the building envelope (walls and roof). Thermal images were made using a FLIR ThermaCAM® E series camera. Based on the qualitative interpretation of the thermal scans, wall areas were selected for invasive examination. At each location the brick veneer was removed to expose the method of brick installation and the composition of the envelope. Exterior sheathing was removed to expose the framework, batt insulation, vapor barrier, and backside of the gypsum wallboard for visual examination. Observations were photographed and the free water content of building components was measured. Microbial colonization was observed and in some cases with deteriorating building components. Air sampling for culturable fungi was conducted throughout the building to determine if the mold present in “visually inaccessible spaces” migrated into the tenant space.
This investigation demonstrates that qualitative thermography coupled with quantitative substantiation is the most powerful method of moisture analysis in building envelopes.
162
INFRARED IMAGING IN RAPID RESPONSE EVALUATIONS: AKA FOUR HURRICANES IN SIX
WEEKS, AN ASSESSMENT RETROSPECTIVE.
L. Rogers, M. Hodgson, S. Donham, Clayton Group Services, Tampa, FL.
When faced with excessive water intrusion in large facilities, time is of the essence to identify water impacted materials before they become fungally impacted materials. Rapid identification of wet materials can also accelerate the effective drying process of the building and ultimately can help contain insurance claim costs. Moisture meters have been the benchmark tool for moisture evaluations. However, the meters are limited since they only provide location specific data, may be confounded by finish material treatments, and are influenced by environmental conditions. The use of infrared imaging can provide a big picture image of a space that can be calibrated to the conditions in the space for a rapid identification of suspect wet materials. This technique, combined with moisture meter confirmation can provide qualitative and quantifiable information about the extent of damage. This presentation will discuss the advantages and disadvantages of each method and present a case study of the implementation in response to the 2004 hurricane season in Florida.
163
METHODS FOR ASSESSING MOISTURE AND REMEDIATING MOLD CONTAMINATION IN HVAC
SYSTEMS.
P. Haas, D. Zehnter, A. Grdina, M. Snyder, Morse Zehnter Associates, West Palm Beach, FL; R. Morse, AIA, Morse Zehnter Associates, Poestenkill, NY.
Mold does not ordinarily grow on surfaces inside HVAC units and ductwork despite the fact that the air inside these units is at essentially 100% relative humidity. This is because the wall of the unit is warmer than the airstream and above the dew point of the air in the airstream. This session will present measurements and observations taken in operating air-conditioning equipment that demonstrate these conditions. Water can be stripped off of coils by a rapidly moving airstream. Measurement methods to determine if this is happening will be described. Data will also be presented on conditions that cause mold growth in ductwork. The causes of these conditions will be described. Methods of measuring environmental conditions (temperature, relative humidity, dew point, equilibrium relative humidity, aerosolized water) inside ductwork using simple hand-held devices will be described. This paper also reports on testing to determine feasibility of the treatment of mold contaminated fibrous glass lined ductwork, the remediation methods used, clearance testing methods, and long-term success of the project.
164
A COMPARISON OF HVAC AGE AND CONDITION WITH IEQ COMPLAINTS.
P. Haas, D. Zehnter, Morse Zehnter Associates, West Palm Beach, FL; R. Morse, AIA, Morse Zehnter Associates, Poestenkill, NY.
This paper summarizes occupant complaints of humidity, temperature, moisture intrusion, and mold compared to HVAC equipment age and condition in approximately 500 buildings. The study parameters included datalogging of complaint areas followed by maintenance and mechanical assessments. An engineering evaluation from as-built conditions, mechanical takeoff information, supply configuration, and dehumidification enhancement was compared to complaints. In each case the causes of the complaints were validated using the datalogging information, maintenance assessments, and the engineering evaluation. Corrective action was described by a condition assessment of the functional components of the equipment, redesign considerations, or equipment replacement in accordance with ASHRAE guidelines.
The assessments will be described by categorizing the complaints and equipment as multivariable and weighting them in a linear model. A comparison of the age and actual mechanical conditions to the sets of weighted complaint values will be made. Correlation using the data set of complaints with the marginal condition found in some of the HVAC equipment inspected will illustrate a number of valuable lessons. Occupant values of comfort using temperature and relative humidity as the primary source of negative complaints will be compared to the actual capability of the HVAC to adequately dehumidify occupied spaces. Complaints made about temperature fluctuations and humidity was often correlated negatively with datalogging values. Occupants were generally less capable of describing a higher temperature and lower relative humidity as more comfortable than lower temperatures coupled with excess relative humidity during occupied hours, even when datalogging values showed this condition. Moisture intrusion and mold infestation complaints were often linked to building envelope conditions and less likely correlated to HVAC equipment ability to treat high humidity. Complaints made of musty odors or visible mold in the absence of building envelope problems existed were often the only way occupants noted high humidity caused by HVAC equipment.
165
POST REMEDIATION AIRBORNE MOULD CONCENTRATIONS IN BUILDINGS FORMERLY USED AS
MARIJUANA GROW OPERATIONS.
J. Rygnestad, Levelton Consultants Ltd., Nanaimo, BC, Canada; G. Krstic, Hemerra Envirochem Inc., Vancouver, BC, Canada.
The effectiveness of correct remedial methods in reducing the level of airborne mould spores in buildings formerly used as marijuana grow operations was explored in this analysis of 126 indoor and 66 outdoor air samples collected at 27 different sites. The data collected was statistically analyzed to determine the probable form of the relationship between indoor and outdoor airborne mould spore concentrations. Post remediation air samples collected from indoor and outdoor environments were similar in both composition and relative frequency. The lack of statistically significant differences in composition or relative frequency between indoor and outdoor samples indicates that correct remedial methods are effective in reducing the level of airborne mould spores in buildings formerly used as marijuana grow operations.
Posted May 30, 2005