Two approaches for evaluating potential health impact from short-term (I ho
ur) inhalation exposure to air emissions from combustion facilities are pre
sented: This information was included as part of the health risk assessment
(HRA) conducted for each proposed facility in conjunction with regulatory
requirements for obtaining an operating permit. Since the facilities being
evaluated have either not yet been constructed or are not yet operational,
air concentrations (particulate and vapor) must first be estimated using da
ta from similar and operational facilities. A chemical's modeled air concen
tration was then compared to its acute toxicity value (ATV) selected from e
stablished Occupational Exposure Limits (OEL) or acute toxicity databases,
if available. Analogous to the current USEPA approach for estimating noncan
cer health effects, acute hazard quotients (AHQs) were summed and compared
to a level of one. When the summation of the AHQs exceeded unity, the chemi
cals were separated by target organ and health effects based on acute expos
ures. The author recognizes that the use of OELs has its limitations. Howev
er, due to the lack of acute toxicity data and the advantage of the complet
eness of the databases for OELs, this approach may be the best way to evalu
ate for acute health concerns for the more than 70 compounds that may be em
itted from these facilities.