Featured Writer:  Public Library Closes Down For Mold Investigation by Rachel L. Adams Certification Arrives For Mold Work EPA Updates Radon Risk Data In New Home Guide by Douglas Kladder

Indoor Environment Connections Featured Writer Public Library Closes Down For Mold Investigation  by Rachel L. Adams, Owner, Indoor Management Inc., Greenfield, Indiana Last September, Indoor Air Management Inc. was contacted to perform an on-site inspection of the Westfield Public Library located in Westfield, Ind. Chronic moisture problems and employee complaints prompted the request for indoor air quality testing to be completed. The high moisture levels also raised concerns for the library's book collection. The original structure was a one-story, 11,830 square foot wood-framed building that was constructed in 1983. In 1995, a 12,695 square foot addition was added to the original structure and was designed to match the original exterior. The exterior cladding consists of a four-inch-thick stone veneer and the windows are insulated wood-clad double-glazed windows. The 4/12-pitch roof is a standard 3-tab fiberglass shingled design. Ventilation vents are incorporated in the soffits and heat strips are installed on the West elevation drip edge. Inspection The initial inspection revealed significant mold growth and moisture inside the building. The areas that were most affected were the West, South, and East exterior walls. There was visible mold growth present on the wood window trim, behind the cove base of exterior walls as well as behind vinyl wall coverings that were peeling from the walls. Visible mold growth was noted on the back side of the air diffusers in several areas of the library. There was condensation present on the inside of the wall-mounted fire alarm boxes as well as water dripping from the window trim of the exterior West wall. The moisture readings were collected with a Dri-eaz nonpenetrating meter and a penetrating Demhorst moisture meter. The majority of the West wall gave readings of >40 percent, using a nonpenetrating meter. The South and East walls had several areas of moisture content above the normal range for those building materials. Data log devices were placed at several areas of the library to monitor and record daily temperature and humidity readings. The readings ranged as high as 80°F and 85 percent RH. Moisture readings were randomly collected from several books located throughout the library. The normal moisture content for books kept in a library institution should be between 6 percent and 8 percent1. Several books contained a moisture content of >15 percent. Following the initial inspection, approximately 40 dehumidifiers were placed in the library, which then removed more than 1,000 gallons of water from the air in the first 24 hours. HEPA air scrubber equipment was also placed throughout the library to provide a minimum of four complete air exchanges per hour in an additional effort to remove contaminants from the indoor environment. Building Systems There were several building systems that failed, which contributed to the excessive moisture inside the building resulting in mold growth. The evaluation of the building structure by an engineering firm identified the following primary problem areas: Three separate construction errors of the roof caused ice damming as well as improper attic ventilation The one-inch air space that should exist between the stone veneer and the interior wood framing in the exterior wall sections had been filled in with mortar, preventing wall ventilation and resulting in exterior moisture being drawn into the wall cavity. This condition leads to high interior humidity levels and creates an unhealthy indoor environment. Improper installation of the building windows opened a direct path for moisture to enter into the building interior. The evaluation of the HVAC units revealed that one unit could not effectively remove the moisture from the air, and thus, high humidity levels throughout the building fostered mold growth. Samples Collected A detailed sampling plan was written and followed in order to provide an accurate assessment of the indoor air quality. Volumetric Samples There were 13 volumetric air samples collected from different locations throughout the library. These samples were collected using an Andersen-N6, Single-Stage Viable Impact sampler in conjunction with a high-volume air pump. Samples were collected over a 3-minute time period at an airflow rate of 1 cubic foot per minute (cfm) and impacted onto Malt Extract agar for culture. All plates were incubated at room temperature for 72 to 120 hours before analysis. Results of volumetric sampling have been reported in colony-forming units per cubic meter of air (CFU/m3). The rule of thumb for evaluating air sample data is to compare the types and total concentration of the indoor samples to the outdoor reference sample. What is identified in the indoor environment should be very similar to what is found in the outdoor sample. This is because of mold entering the indoor environment through HVAC systems and through doors and windows, and mold being carried into the indoors by occupants. The concentrations of total mold found indoor samples should be significantly less than what is identified in the outdoor reference sample because most indoor environments are at a slightly positive pressure due to heating and cooling of the indoor space. It is important to remember that air samples are only a snapshot of the indoor conditions at a specific time of day, activity level, and season of the year. These results will vary with changes in the environment and are only used as a diagnostic tool for evaluating the indoor air quality and possible toxic exposure issues. In the case here, the outside reference sample contained a total fungal concentration of >30,923 CFU/m3, with Cladosporium spp. predominating. Also identified was Alternaria spp., Epicoccum spp. and a small amount of Penicillium spp. Although the total concentration is high, the types of mold identified is typical for outdoor air. In the samples collected throughout the library, Penicillium spp. was the predominant mold identified, and in six samples, it was the only mold type identified. This indicates an imbalance in the indoor air allowing growth of an indicator species of mold. Surface Contact Samples Several surface samples were collected by pressing Rodac surface plates containing Malt Extract agar onto a selected area containing visible mold growth. The four molds identified from several areas of the library were Penicillium spp., Aspergillus nidulans, Aspergillus niger and Stachybotrys chartarum. The majority of these samples were collected from visible mold growth on the window trim, behind cove base, inside wall cavities and behind vinyl wall coverings. Bulk Samples Several bulk samples were collected and consisted of drywall, insulation, vinyl wall coverings and insulation from inside the HVAC unit. All samples were reported as >50 CFU/in2 due to excessive growth. The primary molds identified from these building materials were Penicillium spp., Aspergillus niger, Aspergillus nidulans, Pithomyces spp. and Stachybotrys chartarum. Surface Swab Samples Sterile swabs were used to collect samples from different surfaces such as air diffusers, inside air duct louver, behind cove base and from library books. All samples were reported as >200 CFU/in2 with Penicillium spp. as the predominant fungi. Also identified was Curvularia spp., Acremonium spp., Acremonium spp., and Cladosporium spp. Air-O-Cell Cassettes There were six samples collected using a unique sampling device designed for the rapid collection and analysis of a wide range of airborne particles, including fungal spores. Samples are analyzed via light microscopy at 600x magnification in which the entire sample is analyzed and reported as a total (viable and nonviable spores). Although this sampling technique does not allow for the differentiation between Penicillium and Aspergillus species, it does allow for the identification of Stachybotrys. The types of molds identified in the samples collected throughout the building were Penicillium/Aspergillus and Stachybotrys. Mycotoxin Analysis There were several library employees who had experienced health effects that were suspected to be related to a toxic mold exposure. It was requested that samples be collected for mycotoxin analysis and used for medical evaluations. The samples collected for this analysis were bulk samples that came from areas containing the heaviest amounts of mold contamination in air samples. These areas presented the highest risk for a toxic exposure to the employees as well as the patrons. The samples were taken through an extraction process to recover any mycotoxins present. They were then analyzed by HPLC (high-performance liquid chromatography) for identification and quantification. Mycotoxins are nonvolatile, relatively low-molecular weight secondary metabolic products that may affect exposed persons in a variety of ways. These compounds are considered secondary metabolites because they are not necessary for fungal growth and are simply a product of the primary metabolic processes. The functions of mycotoxins have not been clearly established, but they are believed to play a role in eliminating other microorganisms competing in the same environment. They are also believed to help parasitic fungi invade host tissues2. The amount of toxins needed to produce adverse health effects varies widely among toxins, as well as each person's immune system. Fungi that produce mycotoxins are referred to as toxigenic fungi. The most frequently studied mycotoxins are produced by species of Aspergillus, Fusarium, Penicillium, Stachybotrys and Myrothecium. However, toxins have been detected from many other fungi under certain growth conditions. The kinds and amounts of toxin produced depend on the fungal strain, the growing conditions, as well as the presence or absence of other organisms. Mycotoxins accumulate on fungal spores, cell fragments, and substrates (nutrient source). Fungi that produce potent mycotoxins are seldom abundant in outdoor ambient air. Most toxic exposures occur from indoor growth of fungi related to excessive moisture. Some mycotoxins are carcinogenic, some are vasoactive, and some cause central nervous system damage. Often, a single mycotoxin can cause more than one type of toxic effect. In the library, the mycotoxins present in the greatest concentrations were Sterigmatocystin, Satratoxin H and Roridin E. Although there were 14 target compounds identified as the primary mycotoxins of interest, there were other tentatively identified compounds (TICs) that were also present, such as Atranones, Mytoxins and Stachybotryamides. Remediation Protocol Indoor Air Management Inc. was contracted by the library board of directors to provide the remediation protocol for the remediation company to follow, as well as to monitor the project to ensure a successful outcome. The remediation recommendations are summarized as follows: The remediation must be completed by professionals that have experience and are trained in the safe and effective removal of microbial contamination. They must also have an internal safety / respirator program in place to ensure all personnel are trained in the proper use of personal protective equipment (PPE) as required by OSHA. All personnel performing the remediation must wear full PPE. Books must be processed through a completed cleaning procedure that includes HEPA vacuuming. Any books with a moisture content higher than that recommended by MBK consulting must be dried to a normal moisture content prior to pack-out and storage. The HVAC system must be disabled with critical barriers in place on all registers and vents. Any insulated ductwork must be removed and replaced with galvanized metal ducts along with a complete maintenance schedule for all units. The Specifications stated in the HVAC report provided by the ventilation expert must also be implemented. Control of the humidity and temperature in the building must be maintained during the entire remediation project3. The remediation contractor is responsible for providing the equipment and monitoring protocol to achieve, maintain, and monitor the indoor conditions. Containment erected from 6-mil polyethylene sheeting and/or temporary walls will be constructed to contain all contamination inside the contained areas. A partial pressure differential of 5 - 7 pascal will be used to establish and maintain the contained area. The floor plan provided by the library was used to determine how the building is sectioned off for erection of containment. All porous materials that are supporting mold growth will be removed and disposed of in double 6-mil plastic bags prior to removal from the building. The porous materials include but are not limited to drywall, cove base, insulation, wood trim, ceiling tiles and carpet. Following the complete removal of all contaminated building materials, a HEPA "sandwich" cleaning protocol will be performed which includes HEPA vacuuming and damp wiping with a detergent and minimal water. Wood framing must be cleaned by means of an abrasive technique such as sanding or wire brushing followed by drying to a normal moisture content. Following the completion of the remediation procedures, the structural components must be analyzed and corrections should be recommended by the structural engineer contracted to correct the structural flaws. It is critical for these corrections to be identified and implemented to prevent a re-occurrence of these same moisture problems. The remediation of this public library is currently in progress. A follow-up of containment photographs as well as verification sample results and structural modifications will be presented in a subsequent article. It is very important that all of the appropriate experts participate in a remediation project to ensure the complete and safe removal of mold-contaminated materials. The liability issues that are a normal part of these projects are greatly minimized by establishing the correct protocols and ensuring they are completed. Verification samples at the completion of the project can provide the remediation professional as well as the IAQ expert with final assessment of a successful remediation. References "The Effect of Moisture on Paper", Helen U. Kiely, March 5th, 1927, American Writing Paper Co. Bioaerosols; Assessment and Control; ACGIH, Cincinnati, OH 1999 IICRC Standard and Reference Guide for Professional Water Damage Restoration, S500 - Second Edition, Vancouver, WA 1999 Rachel L. Adams is vice president of MSA Restoration and owner of Indoor Air Management Inc. in Greenfield, Ind. She has provided technical consulting, sampling services and education for indoor air quality and mold remediation projects over the past five years. She is also currently involved with Bolden's Manufacturing and the research associated with the innovative Hydrolab. The research will test and measure microbial contamination of different building materials in water-damaged structures. You can reach her by calling (317) 894-0861.

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Certification Arrives For Mold Work While there continues to be an influx of new training courses on mold and microbial issues, the American Indoor Air Quality Council (AmIAQ) recently set the bar up a notch and introduced the industry's first certification for mold remediation. The Certified Mold Remediation Supervisor (CMRS) program specifically addresses the mitigation and/or remediation of molds, bacteria, yeast, etc. found in buildings. CMRS applicants will be required to have two years experience in microbial or a similar remediation field. including conducting IAQ microbial investigations, doing mitigation/remediation spec writing, performing project management tasks and, of course, conducting the actual mitigation and/or remediation. The first study/review course and examination was to be held at the end of this month in Syracuse, N.Y., with a second course to be held next month in Orlando, Fla., Feb. 9-11. Both courses will be conducted by Bob Krell, president of IAQ Technologies Inc in Syracuse. In addition, there will be three other AmIAQ-approved training centers will provide study/review materials and proctor the examination. According to Charles Wiles, executive director of AmIAQ, the other training providers will be announced next month. "This certification examination was developed 'from the ground up' as a microbial remediation certification," Wiles told IE Connections. "Training providers will develop all new study/review courses that specifically address microbial remediation." The 20-hour CMRS course will cover basics on microbial assessment, project design and monitoring and public relations, but the primary focus will be on remediation. The CMRS examination will be a four-hour examination of 100 questions, each question having five possible answers. "It will be very difficult for the inexperienced to pass," Krell told IE Connections. The 20-hour class will encompass the information covered on the certification exam, along with a wealth of practical knowledge for practitioners. The CMRS program is geared towards individuals with basic knowledge and experience in either microbial remediation or a related field. For more CMRS information or to register for next month's course, call IAQ Technologies at (800) 788-2446 or go to www.iaqcouncil.org.

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EPA Updates Radon Risk Data In New Home Guide by Douglas Kladder, President, CVC, Inc., Colorado Springs, Colorado Last November, EPA released a revised edition of the their Home Buyer's and Seller's Guide. This document has been one of the primary tools that real estate professionals have used in disclosing information about radon at the time of sale. It has also been a tool that many radon professionals have used in providing information to prospective clients. Although much of the document remains unchanged from its earlier 1993 edition, EPA has updated the health risk data to reflect recent radon risk estimates: "Based upon information contained in the National Academy of Science report, The Health Effects of Exposure to Indoor Radon, radon is estimated to cause between 15,000 and 22,000 lung cancer deaths per year". This represents a significant increase (as much as 57 percent) over the 14,000 annual U.S. death rate reported in the previous guide. Homebuyers will find an expanded section regarding the advisability of having radon control techniques incorporated into the construction of new homes. However, there are a few new items that will be of specific interest to radon professionals since they do not appear to be within current EPA protocols: The guide suggests new tests be conducted if the previous tests were not conducted within two years before the sale of the property. The guide also indicates a prohibition of testing in hallways of residential structures, which is not a criterion within current testing protocols. In the section regarding methods for preventing or detecting test interference, the new guide suggests "proximity detectors to reveal the presence of people in the room which may correlate to possible changes in radon levels." In addition to conjuring up images of "Big Brother", does such a device exist for radon use? If someone is aware of it, please email me and we will report on it in a future article. Perhaps the most striking aspect of the new Home Buyer's and Seller's Guide is the absence of referrals to EPA's now closed radon proficiency program. Buyers and sellers are advised to contact state radon offices rather than national certification boards. An html version of the document is at: www.epa.gov/iaq/radon/pubs/hmby guid.html Other Radon Program Updates: New Device Evaluation Program The first manufacturer to submit a new radon measurement device through the National Environmental Health Association's new Device Evaluation Program has successfully completed this rigorous review. Onguard Systems, a manufacturer of blind and non-blind continuous radon monitors, received NEHA approval last month. NEHA certified individuals and laboratories may now submit these devices for performance testing and certification. Continuing Education As part of NEHA's commitment to work more closely with training providers, a new procedure was put into place last month whereby all training providers can update and submit their curriculum for approval for use by individuals certified by the National Environmental Health Association's National Radon Proficiency Program in renewing their credentials. Several aspects of this procedure are an enhancement of old EPA approaches. Course reviews by attendees will be posted on NEHA's website and review criteria for distance based courses have been better defined. All currently NEHA approved continuing education courses will expire as of Feb. 28, 2001 unless they are submitted for review before that date. Performance Test Chamber Added To List Blind performance testing was an integral part of EPA's former proficiency program and is a requirement of current national proficiency programs. A second performance test chamber, Radon Measurements Lab, joins Bowser-Mourner as a NEHA certified chamber for blind performance testing. Chambers achieving this certification must have rigorous radon or radon decay product measurement procedures and quality control measures in place, and routinely inter-compare with EPA chambers. Although NEHA approved, individuals should verify chamber certification with some states. Doug Kladder is president of CVC Inc. in Colorado Springs, Colo., which is contracted to administer the NEHA, NRPP and the Western Regional Radon Training Center. You can reach him by calling (719) 632-1215 or by e-mail at dougkladdr@aol.com.

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