Proximate analysis volatiles loss of weight when the fuel sample is burned at two types of some elevated temperature such as 600 or 800C materials fixed carbon the weight loss when the sample is combusted at 950C B/l=8000A+14,500B A =volatiles,fraction of all dry matter lost at 600C B =fixed carbon,fraction of all dry matter lost between 600C and 950C UNEPProximate analysis volatiles fixed carbon loss of weight when the fuel sample is burned at some elevated temperature such as 600 or 800ºC the weight loss when the sample is combusted at 950ºC two types of materials A =volatiles, fraction of all dry matter lost at 600ºC B =fixed carbon, fraction of all dry matter lost between 600ºC and 950ºC