Application Note 401:
US EPA Method 8270D specifies a procedure for the determination of semivolatiles in solid waste and ground water samples. The long list of analytes includes compounds of a variety of functionalities. A 0.25 μm df column is commonly used for this method, as it will allow for a short analysis time. However, the thin phase film of this dimension limits its sample capacity. An alternative choice is a 0.50 μm df column, which can accommodate higher concentrations and thus extend the calibration range.