Penelitian ini dilakukan untuk menganalisis konsentrasi PM2.5, CO dan CO2 dalam ruangan ketika dilakukan penggunaan bahan bakar biopelet pada sebuah kompor biomassa, serta menghitung laju konsumsi bahan bakar tesebut. Pengujian menggunakan metode water boiling test (WBT) untuk mensimulasikan proses memasak yang terbagi ke dalam 3 fase, yaitu cold start (CS)/fase dingin, hot start (HS)/fase panas, dan simmering (SM)/fase mendidih. Biopelet dibuat dari limbah sekam dan jerami padi. Pengukuran PM2,5 dilakukan menggunakan low volume air sampler (LVS) yang dilengkapi dengan elutriator untuk memisahkan partikel berukuran di atas 2,5 mikron dan filter fiberglass untuk menangkap partikel berukuran kurang dari 2,5 mikron pada kecepatan aliran udara 3,5 liter per menit. Sedangkan pengukuran CO dan CO2 menggunakan Portable Air Quality Monitor. Didapatkan konsentrasi PM2,5 biopelet sekam padi pada fase CS, HS, dan SM berturut-turut 33,13,30,81, dan 24,76 μg/Nm3, sedangkan untuk biopelet jerami padi diperoleh 23,29, 29,98, dan 30,42 μg/Nm3.Terkait konsentrasi CO, pada ketiga fase berturut-turut untuk biopelet sekam padi yaitu 5,29, 5,14, dan 6,09 ppm, sedangkan untuk biopelet jerami padi didapatkan 6,13, 5,86, dan 5,67 ppm. Terakhir, pengukuran konsentrasi CO2 biopelet sekam padi yaitu 436,74, 451,71, dan 472,82 ppm, sedangkan pada biopelet jerami padi terukur 419,87, 417,93, dan 453,43 ppm, pada ketiga fase berturut-turut. Konsentrasi PM2,5, gas CO dan CO2 biopelet masih memenuhi baku mutu udara indoor sesuai dengan PERMENKES/1077/2011. Rasio CO/CO2 berada di bawah nilai 0,02 yang menunjukkan pembakaran bahan bakar biopelet menghasilkan karbon monoksida yang kecil sehingga terjadi pembakaran sempurna. Laju konsumsi bahan bakar biopelet lebih kecil dibandingkan jika digunakan biomassa yang belum diolah menjadi biopelet. ABSTRACTThis research was conducted to analyse indoor PM2.5, CO dan CO2 concentrations during the use of biopellet fuel in a biomass stove, and to calculate the fuel consumption rate. Water boiling test (WBT) was used to simulate cooking activities, which comprises of three phases, i.e., cold start (CS), hot start (HS), and simmering (SM). The biopellet was made from rice husk and straw wastes. PM2.5 were measured by using a low volume air sampler (LVAS) that was equipped with an elutriator to separate particulates with more than 2.5-micron size and a fiberglass filter to trap particulates with less than 2.5-micron size at air flow rate of 3.5 liter per minute. Meanwhile, a portable air quality monitor was used to measure CO dan CO2. It was found that PM2.5 concentrations for rice husk biopellet during CS, HS, and SM were, respectively, 33.13,30.81, and 24.76 μg/Nm3. While those for rice straw biopellet were 23.29, 29.98, and 30.42 μg/Nm3. Regarding CO concentrations during the three phases for rice husk biopellet were, respectively, 5.29, 5.14, and 6.09 ppm, whilst for the rice straw biopellet the concentrations were 6.13, 5.86, and 5.67 ppm. Lastly, the CO2 measurements for rice husk biopellet were 436.74, 451.71, and 472.82 ppm, while those for rice husk biopellet were 419.87, 417.93, and 453.43 ppm, during the three phases correspondingly. All PM2.5, CO and CO2 gas concentrations still met indoor air quality standard, in accordance with Minister of Health Regulation Number 1077/2011. Moreover, the CO/CO2 ratios were below 0.02, which indicates that the combustion of the biopellet fuels emited small amount of carbon monoxide, thus, perfect combustion were achieved. The biopellet fuel consumption rates were smaller than those of virgin biomasses that had not been converted into biopellet