The contribution of interstitial injection induced by P and B diffusion (DII) under nonoxidizing conditions to the gettering process is discussed by considering a short-range (doped-layer) effect and a long-range (bulk) effect. We show that : (i) the positive gradient of the concentration profile of the silicon interstitials within the highly doped layer is favorable for the gettering of the substitutional metallic species via a kick-out mechanism both during P and B diffusion in silicon; (ii) the contribution of DII to the gettering of 3d elements in silicon is significant only within the highly P-doped layers (short-range effect); (iii) the predictions of DII induced gettering model agree with the experimental evidence on P diffusion gettering of Co and on P diffusion gettering and B diffusion gettering of Au in silicon.