Contribution from radon in natural gas to the dose from airborne radon daughters in homes.

Data has been obtained on the radon concentration in natural gas supplied to several metropolitan areas in the United States. The average value of 20pCi/l was selected to estimate the contribution of this source of natural radioactivity to doses from radon daughters received by individuals in homes. Radon daughter concentrations in the home atmosphere were calculated by use of computer programs for an 800 cu.ft. house in which 27 cu.ft. of gas per day was used for cooking in an unvented kitchen range. The contribution to total dose to the bronchial epithelium from the radon and daughters in natural gas averaged 3%. There was a 3.5% decrease in total estimated dose when the air change rate increased from 0.25 to 2.0 per hour.