In order to adequately understand the effects that energetic particle precipitation bears on radio wave absorption, we have analysed cosmic noise absorption (CNA) measured by the imaging riometer at Kilpisjarvi, Finland (IRIS) during 1996-2011. We analysed periods of co-rotating interaction regions(CIR) occurring as a result of the interaction of high speed solar wind streams emanating from coronal holes. We utilised the superposed epoch analysis method to investigate the absorption signature during these events. We identified periods of maximum CNA enhancement for each of these events and the duration of elevated CNA. Each of these events show differing CNA enhancement periods and elevation thresholds.