G Venkatesh , S Krishnaiah 2 4 (October-December) The work compared the leaching of heavy metals Cr Ni Zn and Pb from the hybrid bricks using the Toxicity Characteristics Leaching Procedure TCLP and Netherlands tank leaching tests Hybrid bricks were prepared by partially replacing clay with an increasing weight percentage of tannery sludge 0 9 18 and 27 by weight of brick specimen and a constant weight percentage 10 by weight of brick of glass powder The prepared mixes were fired to 900oC 950oC and 1000oC to assess the leaching potential of metals from hybrid bricks at different temperatures The TCLP test was conducted as per the United States Environmental Protection Agency USEPA 1311 whereas the Netherlands tank leaching test was performed as per the NEN 7345 standard In both methods the leaching of metals increased with the tannery sludge amounts and decreased with an increase in temperature The release of metals from the TCLP test was slightly higher than that of the Netherlands tank leaching test The higher amounts of metal released from the TCLP test were due to exposure to more areas of particles due to the crushing of particles The results obtained from the TCLP test are more appropriate to the actual field conditions arising in the service life of materials Copyright (c) International Journal of Computational Science and Engineering Research . All rights reserved 2026