Real-time and time-integrated PM2.5 and CO from prescribed burns in chipped and non-chipped plots: firefighter and community exposure and health implications

J Expo Sci Environ Epidemiol. 2006 Jul;16(4):351-61. doi: 10.1038/sj.jes.7500497. Epub 2006 May 31.


In this study, smoke data were collected from two plots located on the Francis Marion National Forest in South Carolina during prescribed burns on 12 February 2003. One of the plots had been subjected to mechanical chipping, the other was not. This study is part of a larger investigation of fire behavior related to mechanical chipping, parts of which are presented elsewhere. The primary objective of the study reported herein was to measure PM(2.5) and CO exposures from prescribed burn smoke from a mechanically chipped vs. non-chipped site. Ground-level time-integrated PM(2.5) samplers (n=9/plot) were placed at a height of 1.5 m around the sampling plots on the downwind side separated by approximately 20 m. Elevated time-integrated PM(2.5) samplers (n=4/plot) were hung atop approximately 30 ft poles at positions within the interior of each of the plots. Real-time PM(2.5) and CO data were collected at downwind locations on the perimeter of each plot. Time-integrated perimeter 12-h PM(2.5) concentrations in the non-chipped plot (AVG 519.9 microg/m(3), SD 238.8 microg/m(3)) were significantly higher (1-tail P-value 0.01) than those at the chipped plot (AVG 198.1 microg/m(3), SD 71.6 microg/m(3)). Similarly, interior time-integrated 8-h PM(2.5) concentrations in the non-chipped plot (AVG 773.4 microg/m(3), SD 321.8 microg/m(3)) were moderately higher (1-tail P-value 0.06) than those at the chipped plot (AVG 460.3 microg/m(3), SD 147.3 microg/m(3)). Real-time PM(2.5) and CO data measured at a position in the chipped plot were uniformly lower than those observed at the same position in the non-chipped plot over the same time period. These results demonstrate that smoke exposures resulting from burned chipped plots are considerably lower than from burned non-chipped plots. These findings have potentially important implications for both firefighters working prescribed burnings at chipped vs. non-chipped sites, as well as nearby communities who may be impacted from smoke traveling downwind from these sights.

Publication types

  • Comparative Study

MeSH terms

  • Air Pollutants / analysis*
  • Carbon Monoxide / analysis*
  • Carbon Monoxide / toxicity*
  • Environmental Exposure*
  • Fires*
  • Forestry*
  • Humans
  • Occupational Exposure / adverse effects*
  • Particle Size
  • Smoke Inhalation Injury / epidemiology*
  • Time Factors


  • Air Pollutants
  • Carbon Monoxide