Same as Fig. 4, but for SNRs (orange) compared to the diffuse ISM (blue). Panels (a) and (b) correspond to R_PAH measurements from the observed and the local background subtracted fluxes. SNRs do not reveal a decrease in R_PAH measured from the observed fluxes indicating that SN shocks are unlikely major contributors to the selective PAH destruction at 50 pc scale. A more localized effect is evident from the background-subtracted measurements.