Measurements of radioactive gases i.e. radon and thoron & their progeny concentration were carried out in some selected dwellings in Rampur and nearby towns of Uttar Pradesh by using Solid State Nuclear Track Detector (SSNTD).The radon-thoron twin dosimeter cups were used for the measurements. The measurement was repeated on a time integrated four quarterly cycles to cover all the four seasons (summer, rainy, autumn &winter) of the calendar year.
 During summer, rainy, autumn and winter seasons the radon concentration was found to vary from 9 Bq/m3 to 55 Bq/m3 with an average of 18.72 Bq/m3, 11Bq/m3 to 40 Bq/m3 with an average of 24.41 Bq/m3, 15 Bq/m3 to 46 Bq/m3 with an average of 29.95 Bq/m3and 25 Bq/m3 to 85 Bq/m3 with an average of 44.92 Bq/m3 respectively where as its progeny concentration varied from 0.57mWL to 5.94mwL with an average value of 2.02mWL, 1.18mWL to 4.32mWL with an average value of 2.63mWL, 1.62mWl to 4.97mWL with an average value of 3.23mWL and 2.70mWL to 9.18mWL with an average value of 4.85mWL respectively.
 The thoron concentration was found to vary from 7.33 Bq/m3 to 22.5Bq/m3 with an average value of 11.86Bq/m3, 10.50 Bq/m3 to 23Bq/m3 with an average value of 16.06 Bq/m3, 11.66 Bq/m3 to 24.5 Bq/m3 with an average value of 17.44 Bq/m3, and 17.66 Bq/m3 to 30 Bq/m3 with an average value of 21.35 Bq/m3 respectively where as its progeny concentration varied from 0.19mWL to 0.60mWL with an average value of 0.32mWL, 0.28mWL to 0.62mWL with an average value of 0.43mWL, 0.31mWl to 0.66mWL with an average value of 0.47mWL and 0.47mWL to 0.81mWL with an average value of 0.57mWL respectively in different seasons.
 All values were observed below the recommended action level (200Bq/m3) set by the various organizations (ICRP, 1993)