Stefanos N Kales1, Denise L Smith2. 1. Environmental & Occupational Medicine & Epidemiology, Harvard School of Public Health, Boston, MA, USA and Occupational Medicine, The Cambridge Health Alliance/Harvard Medical School, Cambridge, MA, USA Health and Exercise Sciences, Skidmore College, Saratoga Springs, NY, USA and University of Illinois Fire Service Institute, Champaign, IL, USA skales@hsph.harvard.edu dsmith@skidmore.edu. 2. Environmental & Occupational Medicine & Epidemiology, Harvard School of Public Health, Boston, MA, USA and Occupational Medicine, The Cambridge Health Alliance/Harvard Medical School, Cambridge, MA, USA Health and Exercise Sciences, Skidmore College, Saratoga Springs, NY, USA and University of Illinois Fire Service Institute, Champaign, IL, USA.