\begin{table}%t3 \caption{\label{table:EBL_estimates}Estimated level of the CIRB for the individual fields.} \small%\centerline { \begin{tabular}{lrrr} \hline \hline Field & $I$(90 $\mu$m) & $I$(150 $\mu$m) & $I$(180 $\mu$m) \\ & (MJy~sr$^{-1}$) & (MJy~sr$^{-1}$) & (MJy~sr$^{-1}$) \\ \hline \hline EBL22 & --2.16 (1.04) & 0.53 (0.52) & 0.91 (0.47) \\ EBL26$^1$ & --1.28 (3.05) & --1.53 (1.73) & 0.29 (1.53) \\ NGP & 0.35 (0.74) & 1.15 (0.37) & 1.48 (0.28) \\ average & --0.54 (0.65) & 0.83 (0.41) & 1.26 (0.37) \\ \hline \end{tabular}} \medskip The values correspond to the difference between the offsets listed in Table~\ref{table:fit} and the ZL estimates of Table~\ref{table:ZL_estimates}. No colour correction was applied. The 1-$\sigma$ estimated statistical errors are given in parentheses (see text). \\ $^1$~Fit to data with $W({\rm HI})<$ 200~K~km~s$^{-1}$ only. \end{table}