Spectral energy distribution (SED) of OH 231.8 showing the continuum emission flux measurements from the individual SPWs observed in this project (Table 1). The dashed line represents the best-fit power law of the continuum flux. The outlier at 216.7 GHz (nearest to 1400 μm) has very large errorbars possibly reflecting a calibration problem or some contamination by H2S line emission.