 A National Energy Board study assumed a standard dilbit containing 33% condensate (resulting in product with "21.5 °API and sulphur content of 3.3 percent") and synbit containing 50% SCO.By selecting different diluent types and blend ratios, bitumen shippers attempt to lower component costs, increase blend value, and maintain pipeline transportability.The blend ratio may consist of 25 to 55% diluent by volume, depending on characteristics of the bitumen and diluent, pipeline specifications, operating conditions, and refinery requirements.