One of the main sources of organic carbon (OC) aerosols is biomass burning. Therefore, it is important to be able to determine the contribution of biomass burning to the total OC concentration. Smoke marker measurements provide one of the most common methods to make this determination. The key in using the smoke marker approach is knowing the ratio of the smoke marker to the total OC concentration at the source. However, there is still much uncertainty in these ratios, especially for biomass burning emissions from prescribed burning and wildfires. Therefore, the goal of this work is to try to better constrain smoke marker ratios at the source for this type of burning. Comparisons of samples collected from five sets of prescribed burns and multiple wildfires across the U.S. will be made to source samples collected at the Fire Science Lab in Missoula, MT from the FLAME (Fire Laboratory at Missoula Experiment) studies. Data for smoke markers such as levoglucosan, mannosan, galactosan, and potassium will be presented. How sampling location, fuel type, and burning conditions affect these ratios will also be explored.