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Applied and Environmental Microbiology. 71 (9) 5399-5403. Purchase this publication. Effect of Chlorine Dioxide Gas on Fungi and Mycotoxins Associated with Sick Building Syndrome S. C. Wilson,* C. Wu, L. A. Andriychuk, J. M. Martin, T. L. Brasel, C. A. Jumper, and D. C. Straus Center for Indoor Air Research, Department of Microbiology and Immunology, Health Sciences Center, Texas Tech University, Lubbock, Texas 79430 Received 28 October 2004/ Accepted 28 March 2005 The growth of indoor molds and their resulting products (e.g., spores and mycotoxins) can present health hazards for human beings. The efficacy of chlorine dioxide gas as a fumigation treatment for inactivating sick building syndrome-related fungi and their mycotoxins was evaluated. Filter papers (15 per organism) featuring growth of Stachybotrys chartarum, Chaetomium globosum, Penicillium chrysogenum, and Cladosporium cladosporioides were placed in gas chambers containing chlorine dioxide gas at either 500 or 1,000 ppm for 24 h. C. globosum was exposed to the gas both as colonies and as ascospores without asci and perithecia. After treatment, all organisms were tested for colony growth using an agar plating technique. Colonies of S. chartarum were also tested for toxicity using a yeast toxicity assay with a high specificity for trichothecene mycotoxins. Results showed that chlorine dioxide gas at both concentrations completely inactivated all organisms except for C. globosum colonies which were inactivated an average of 89%. More than 99% of ascospores of C. globosum were nonculturable. For all ascospore counts, mean test readings were lower than the controls (P < 0.001), indicating that some ascospores may also have been destroyed. Colonies of S. chartarum were still toxic after treatment. These data show that chlorine dioxide gas can be effective to a degree as a fumigant for the inactivation of certain fungal colonies, that the perithecia of C. globosum can play a slightly protective role for the ascospores and that S. chartarum, while affected by the fumigation treatment, still remains toxic. * Corresponding author. Mailing address: Dept. of Microbiology and Immunology, TTUHSC, 3601 4th St., Lubbock, TX 79430. Phone: (806) 743-2466. Fax: (806) 743-2334. E-mail: stephen.wilson@ttuhsc.edu . Visit http://aem.asm.org/ to purchase a full length publication on this topic. Applied and Environmental Microbiology, September 2005, p. 5399-5403, Vol. 71, No. 9 0099-2240/05/$08.00+0     doi:10.1128/AEM.71.9.5399-5403.2005 Copyright © 2005, American Society for Microbiology. All Rights Reserved. ASHRAE Trasactions Vol 111. Part 1. p 85-87. Purchase this publication at the ASHRAE Store. 4749 - A Survey Technique for Evaluating Heating, Ventilating, and Air-Conditioning Systems This paper presents a survey technique for rating HVAC systems. System components are grouped into categories. The components inside the categories are numerically rated from 1.0 to 5.0 in terms of mechanical system maintenance, service performance, and operation efficiency of the mechanical equipment. The component scores are averaged for each category. These scores are then averaged to give a single score for the whole system. To evaluate the consistency of survey ratings, a trial was conducted whereby on the same day, ten independent assessors with different years of job experience examined a range of equipment from two major HVAC systems (N = 200). A Cronbach’s Alpha Internal Consistency Analysis of the averaged ratings gave a result of 0.76, indicating good agreement between assessors. These data show that apart from being able to reduce large datasets into a concise summary, the survey technique is robust and internally consistent. AUTHORS: H.W. Holder; W.S. Willis; S.C. Wilson, PhD; M.D. Larranaga, PhD; D.C. Straus, PhD NO. OF PAGES: 5 PAGES: 85-87 PUBLISH DATE: 2005, Winter Meeting PUBLISHER: ASHRAE UNITS: SI