This book is a comprehensive source for technical information regarding ultra- oletgermicidalirradiation(UVGI)anditsapplicationtoairandsurfacedisinf- tion for the control of pathogens and allergens. The primary focus is on airborne microbesandsurfacecontaminationapplications.Water-basedapplicationsarenot addressedhereexceptincidentallyastheyrelatetoairandsurfacemicrobes,since manyadequatetextsonwater-basedUVdisinfectionareavailable.Allaspectsof UVGIsystems,includingdesignmethods,modeling,safety,installation,guidelines, anddisinfectiontheoryareaddressedinsuf?cientdetailthatnoadditionalsources needbeconsulted.Itishopedbytheauthorthatprovidingthisinformationinone singlevolumewillsimplifythedesignandinstallationofUVGIsystems,helpgu- anteeeffectiveperformanceofnewsystems,andfacilitatetheiruseonawidescale forthepurposeofimprovinghumanhealthandcontrollingepidemicdisease.This book is organized to provide systematic coverage of all essential issues and will serveequallywellasbothatextbookandahandbookforgeneralreference. Any readers who ?nd technical errors or omissions in this book may to send themtomeatdrkowalski@aerobiologicalengineering.com.Erratawillbepostedat http://www.aerobiologicalengineering.
com/UVGI/errata.htm. All other corresp- denceshouldbesenttodrkowalski@ibsix.com. vii Acknowledgements I gratefully acknowledge all those who assisted me in the research, preparation, andreviewofthechaptersinthisbook,includingWilliamBahn?eth,SteveMartin, Chuck Dunn, Jim Freihaut, Dave Witham, Ed Nardell, Richard Vincent, Mark Hernandez, Ana Nedeljkovic-Davidovic, Clive Beggs, Renzhou Chen, Normand Brais, Katja Auer, Warren Lynn, Mike Sasges, Bill Carey, Tatiana Koutchma, Forrest Fencl, Russ Briggs, Josephine Lau, Carlos Gomes, Fahmi Yigit, Herbert Silderhuis, Joe Ritorto, Merrill Ritter, Brad Hollander, Scott Prahl, Karl Linden, WilliamBalch,AtanuSengupta,M.D.Lechner,KetanSharma,DonaldMilton,and especially Mary Clancy all the members of the IUVA Air Treatment Group who supported the UV Guidelines project, and also Linda Gowman, Jim Bolton and everyone in the International Ultraviolet Association who sponsored the UV Air TreatmentGroup.AspecialthanksgoestoAliDemirciandRaymondSchaeferfor theircontributionstothechapteronPulsedUVSystems.Iespeciallythankmyp- ents,StanleyJ.KowalskiandMarylaKowalski,andmysisterVictoriaChorpenning fortheirunwavering supportandencouragement duringthesepastfewyearsasI recoveredmyhealthandreturnedtoresearch.