National scale air toxics assessment air toxics cancer risk:NFr:Pt:^Patient:Qn
national scale air toxics assessment air toxics cancer risk:nfr:pt:^patient:qn
National scale air toxics assessment air toxics cancer risk:Number Fraction:To identify measures at a point in time:^Patient:Quantitative
national scale air toxics assessment air toxics cancer risk:number fraction:to identify measures at a point in time:^patient:quantitative