SUMMARY:An investigation of the effect of various sanitizers, including kinds containing hypo‐chlorite, formaldehyde and quaternary ammonium compounds, alone and with detergents, and of a nonionic detergent alone, on the cleanability by various methods of commercial wooden fish boxes, showed that no major reductions in viable counts greater than 99·9% could be expected; this was due presumably to the high degree of contamination of the box and the porous nature of the wood. Of the materials investigated, hypochlorite solutions containing not less than 1,000 p/m of free chlorine and the quaternary ammonium compounds in 0·1–1% concentrations were most satisfactory. The implications of these investigations, to the fish industry in particular and to the cleanability of wooden surfaces in general, are disc