2. Estimating radon exposure by performing one calculation using the highest pre-mitigation radon test result obtained by any affiliate and the maximum total time spent by any affiliate in buildings while conducting mitigations for the past year, or if a new business, by estimating radon exposure at six months and one year during the first year of certification, using the following calculation: WLM per year = (exposure (WL) x hours exposed per year) /170 hours per month
(Assumes one month of work = 170 hours)
ER = (WL x 100)/ pCi/L
For radon mitigation, if the equilibrium ratio (ER) is not given, it is assumed to be 100 percent; which means that the ER = 1.0.
1 =(WL x 100)/ pCi/L
WL =(pCi/L)/ 100