QuanTech Inc.

Arlington, VA, United States

QuanTech Inc.

Arlington, VA, United States
SEARCH FILTERS
Time filter
Source Type

Vesper S.,U.S. Environmental Protection Agency | Barnes C.,Childrens Mercy Hospital | Ciaccio C.E.,Childrens Mercy Hospital | Johanns A.,San Diego Lead Safety and Healthy Homes Program | And 6 more authors.
Journal of Asthma | Year: 2013

Objective. Mold in water-damaged homes has been linked to asthma. Our objective was to test a new metric to quantify mold exposures in asthmatic children's homes in three widely dispersed cities in the United States. Methods. The Environmental Relative Moldiness Index (ERMI) metric was created by the US Environmental Protection Agency, with assistance by the Department of Housing and Urban Development (HUD), to quantify mold contamination in US homes. The ERMI values in homes of asthmatic children were determined for the three widely dispersed cities of Boston, Kansas City, and San Diego. Results. Asthmatic children in Boston (n = 76), Kansas City (n = 60), and San Diego (n = 93) were found to be living in homes with significantly higher ERMI values than were found in homes randomly selected during the 2006 HUD American Healthy Homes Survey (AHHS) from the same geographic areas (n = 34, 22, and 28, respectively). Taken together, the average ERMI value in the homes with an asthmatic child was 8.73 compared to 3.87 for the AHHS homes. In addition, Kansas City homes of children with "Mild, Moderate, or Severe Persistent Asthma" had average ERMI value of 12.4 compared to 7.9 for homes of children with only "Mild Intermittent Asthma." Aspergillus niger was the only mold of the 36 tested which was measured in significantly greater concentration in the homes of asthmatic children in all three cities. Conclusion. High ERMI values were associated with homes of asthmatic children in three widely dispersed cities in the United States. © 2012 Informa Healthcare USA, Inc.


White K.T.,QuanTech Inc. | Dewalt F.G.,QuanTech Inc. | Cox D.C.,QuanTech Inc. | Schmehl R.,QuanTech Inc. | And 2 more authors.
ASTM Special Technical Publication | Year: 2011

A proficiency testing procedure for evaluating the accuracy of lead measurements taken by certified lead-based paint inspectors using portable X-ray fluorescence (XRF) instruments was developed and pilot tested. XRF instruments are widely used for inspection of housing units to determine the presence or absence of lead-based paint. Previous research showed variability between different XRF instruments when used to conduct lead-based paint inspections. Due to concerns over potential errors in inspection reports resulting from biased XRF measurements, a proficiency testing procedure was pilot tested to provide entities, such a state or federal regulators, a means of evaluating the instrumentation being used for lead-based paint inspections. Copyright © 2011 by ASTM International.


Cox D.C.,QuanTech Inc. | Dewalt F.G.,QuanTech Inc. | White K.T.,QuanTech Inc. | Schmehl R.,QuanTech Inc. | And 2 more authors.
ASTM Special Technical Publication | Year: 2011

Multiple pre-cleaned, four-room residential containments were each subjected to a single high-dust generating activity involving lead-based paint. After dust generation, a geometric wipe sampling grid was used, with a target of 8 interior and 8 perimeter samples in each room, to assess dust-lead on the floors. The containment was then cleaned using the "High Efficiency Particulate Air (HEPA) vacuum/3-bucket wet-mop/HEPA vacuum" procedure found in the U.S. Dept. of Housing and Urban Development Guidelines. Post-cleaning (clearance) floor wipe samples were then taken at side-by-side locations to the pre-cleaning samples. It was found that: [1] floor dust-lead along the perimeters of rooms was three times more difficult to clean than dust-lead from the interiors of the rooms; [2] post-cleaning dust-lead loadings tended to be higher along the perimeters of the rooms than in the interiors of the rooms such that clearance failure was much more likely for individual floor samples collected along the perimeters; and [3] four-wipe composite sampling within each room (two randomly selected from the perimeter and two randomly selected from the interior) provided a very reliable method for detecting clearance failure (99% or greater) versus a randomly selected single wipe sample per room (50% or less). Copyright © 2011 by ASTM International.


White K.T.,QuanTech Inc. | Dewalt F.G.,QuanTech Inc. | Cox D.C.,QuanTech Inc. | Schmehl R.,QuanTech Inc. | And 2 more authors.
ASTM Special Technical Publication | Year: 2011

Sample preparation methods for four-wipe composite dust wipe samples, used by nine different laboratories accredited under the U.S. Environmental Protection Agency (EPA) National Lead Laboratory Accreditation Program (NLLAP), were evaluated to select two methods most likely to provide the best overall performance among multiple laboratories, based on accuracy, precision and practicality of the methods. The best performing methods involved (1) hot nitric acid/hydrogen peroxide digestion and (2) nitric acid ultrasonication. In a second round of testing, two sets of composite dust wipe samples with known amounts of lead were submitted blind to each of the nine laboratories to be prepared for analysis using these two sample preparation methods. Results showed that both methods are capable of meeting all EPA NLLAP requirements for accuracy (recovery) and precision. The ultrasonication method had superior performance at lower cost. Copyright © 2011 by ASTM International.


White K.T.,QuanTech Inc. | Dewalt F.G.,QuanTech Inc. | Cox D.C.,QuanTech Inc. | Schmehl R.,QuanTech Inc. | And 2 more authors.
Journal of ASTM International | Year: 2011

A proficiency testing procedure for evaluating the accuracy of lead measurements taken by certified lead-based paint inspectors using portable X-ray fluorescence (XRF) instruments was developed and pilot tested. XRF instruments are widely used for inspection of housing units to determine the presence or absence of lead-based paint. Previous research showed variability between different XRF instruments when used to conduct lead-based paint inspections. Due to concerns over potential errors in inspection reports resulting from biased XRF measurements, a proficiency testing procedure was pilot tested to provide entities, such a state or federal regulators, a means of evaluating the instrumentation being used for lead-based paint inspections. Copyright © 2011 by ASTM International.


White K.T.,QuanTech Inc. | Dewalt F.G.,QuanTech Inc. | Cox D.C.,QuanTech Inc. | Schmehl R.,QuanTech Inc. | And 2 more authors.
Journal of ASTM International | Year: 2011

Sample preparation methods for four-wipe composite dust wipe samples, used by nine different laboratories accredited under the U.S. Environmental Protection Agency (EPA) National Lead Laboratory Accreditation Program (NLLAP), were evaluated to select two methods most likely to provide the best overall performance among multiple laboratories, based on accuracy, precision and practicality of the methods. The best performing methods involved (1) hot nitric acid/hydrogen peroxide digestion and (2) nitric acid ultrasonication. In a second round of testing, two sets of composite dust wipe samples with known amounts of lead were submitted blind to each of the nine laboratories to be prepared for analysis using these two sample preparation methods. Results showed that both methods are capable of meeting all EPA NLLAP requirements for accuracy (recovery) and precision. The ultrasonication method had superior performance at lower cost. Copyright © 2011 by ASTM International.


Vesper S.,U.S. Environmental Protection Agency | Wymer L.,U.S. Environmental Protection Agency | Cox D.,QuanTech Inc. | Dewalt G.,QuanTech Inc.
Science of the Total Environment | Year: 2016

Starting in the 1940s, gypsum drywall began replacing plaster and lathe in the U.S. home construction industry. Our goal was to evaluate whether some mold populations differ in water- damaged homes primarily constructed with gypsum drywall compared to plaster. The dust samples from the 2006 Department of Housing and Urban Development's (HUD) American Health Homes Survey (AHHS) were the subject of this analysis. The concentrations of the 36 Environmental Relative Moldiness Index (ERMI) molds were compared in homes of different ages. The homes (n = 301) were built between 1878 and 2005. Homes with ERMI values >. 5 (n = 126) were defined as water-damaged. Homes with ERMI values >. 5 were divided in the years 1976 to 1977 into two groups, i.e., older (n = 61) and newer (n = 65). Newer water-damaged homes had significantly (p = 0.002) higher mean ERMI values than older water-damaged homes, 11.18 and 8.86, respectively. The Group 1 molds Aspergillus flavus, Ammophilus fumigatus, Aspergillus ochraceus, Cladosporium sphaerospermum and Trichoderma viride were found in significantly higher concentrations in newer compared to older high-ERMI homes. Some mold populations in water-damaged homes may have changed after the introduction of gypsum drywall. © 2016.


PubMed | U.S. Environmental Protection Agency and QuanTech Inc.
Type: | Journal: The Science of the total environment | Year: 2016

Starting in the 1940s, gypsum drywall began replacing plaster and lathe in the U.S. home construction industry. Our goal was to evaluate whether some mold populations differ in water- damaged homes primarily constructed with gypsum drywall compared to plaster. The dust samples from the 2006 Department of Housing and Urban Developments (HUD) American Health Homes Survey (AHHS) were the subject of this analysis. The concentrations of the 36 Environmental Relative Moldiness Index (ERMI) molds were compared in homes of different ages. The homes (n=301) were built between 1878 and 2005. Homes with ERMI values >5 (n=126) were defined as water-damaged. Homes with ERMI values >5 were divided in the years 1976 to 1977 into two groups, i.e., older (n=61) and newer (n=65). Newer water-damaged homes had significantly (p=0.002) higher mean ERMI values than older water-damaged homes, 11.18 and 8.86, respectively. The Group 1 molds Aspergillus flavus, Ammophilus fumigatus, Aspergillus ochraceus, Cladosporium sphaerospermum and Trichoderma viride were found in significantly higher concentrations in newer compared to older high-ERMI homes. Some mold populations in water-damaged homes may have changed after the introduction of gypsum drywall.


Smirnov I.,QuanTech Inc.
Proceedings of the International Astronautical Congress, IAC | Year: 2014

The major goal of space radiation research is to enable the human exploration of space without exceeding limiting risks from space radiation. Space radiation is distinct from common terrestrial forms of radiation because it is comprised of high-energy protons and heavy ions and their secondary produced in shielding and tissue. The proposed study will seek to reduce the uncertainties in risk predictions for cancer and acute radiation risks by utilizing MRET (Molecular Resonance Effect Technology) activated water as a dietary countermeasure to mitigate acute radiation risks. The objectives of the study was focused to show that MRET activated water can be utilized to reduce the risk of DNA damage processing that underlies radiation effects in general. The goal of this investigation was to study the effect of MRET water for the prevention and treatment of two kinds of oncology diseases on mice (laboratory models of Ehrlich's ascites tumor and Sarcoma ascites form). MRET Water is produced with the help of patented (US Patent No. 6, 022, 479), non-chemical Molecular Resonance Effect Technology (MRET). The anomalous electrodynamic characteristics and viscosity of MRET water provide some evidence regarding the possible effect of MRET water on electrical activity and proper function of the cells. The research regarding the physical parameters of water confirmed that MRET treatment of distilled water leaded to substantial modification of basic physical-molecular properties of water. The anomalous viscosity of MRET water (subject to very low tangent pressure) and electrodynamic characteristics of MRET water (subject to applied electromagnetic field of low frequency range) confirm the high level of long-range dynamic structuring of water molecules in polarized-oriented multilayer formations in activated water produced with the help of MRET activation process. The significant positive effect of MRET Activated Water regarding the tumor resistance in animals was observed in all groups of mice on different fractions of MRET water in the experiments conducted on 500 mice at Kiev Institute of Experimental Pathology, Oncology and Radiobiology, Ukrainian Academy of Science. The best results were observed in the groups of mice on MRET water activated for 30 minutes (optimal regime of activation).


A method of changing the response level for any chemical test kits designed for the determination of a metal or compound (such as lead) in paint and other media is disclosed. The invention solves two common problems that exist with using chemical test kits for the detection of lead in paint or other coatings and media: (1) conversion of the paint sample into particles small enough to dissolve the metal in the sample; and, (2) controlling the amount of (paint) sample that gets exposed to the chemicals. This is accomplished by using a coffee grinder or equivalent tool plus a solid (food) product to break up the paint sample into small particles and at the same time dilute the concentration of the metal, while in solid form, down to a level that results in obtaining a positive response at the desired concentration.

Loading QuanTech Inc. collaborators
Loading QuanTech Inc. collaborators