In our previous studies we have used electrolytic conductivity detection (ELCD) in the selective analysis of chlorinated fatty acids in marine samples. In order to determine the chlorinated fatty acids quantitatively, we studied the ELCD response factors (RFs) of chlorinated fatty acids and compared them with those of other chlorinated compounds. We also studied the effect of reactor temperature and total gas flow-rate on the RFs. The ELCD RFs of different organochlorine compounds varied significantly at a reactor temperature of 600°C. The variation was reduced at reactor temperatures higher than 850°C. At low reactor temperatures, the RFs of methyl esters of chlorinated fatty acid were much higher than those of the other compounds. Although the gas flow in the reactor was laminar, diffusion was still rapid enough not to cause the varied RFs. Nitrogen-containing chlorinated compounds had lower RFs than compounds without nitrogen, owing to a neutralization of hydrogen chloride by ammonia. Copyright (C) 1999 Elsevier Science B.V.