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In this paper we present the results of observations of seventeen HII regionsin thirteen galaxies from the SIGRID sample of isolated gas rich irregulardwarf galaxies. The spectra of all but one of the galaxies exhibit the auroral[OIII] 4363A line, from which we calculate the electron temperature, Te, andgas-phase oxygen abundance. Five of the objects are blue compact dwarf (BCD)galaxies, of which four have not previously been analysed spectroscopically. Weinclude one unusual galaxy which exhibits no evidence of the [NII]{\lambda}{\lambda} 6548,6584A lines, suggesting a particularly low metallicity(< Zsolar/30). We compare the electron temperature based abundances with thosederived using eight of the new strong line diagnostics presented by Dopita etal. (2013). Using a method derived from first principles for calculating totaloxygen abundance, we show that the discrepancy between the Te-based and strongline gas-phase abundances have now been reduced to within ~0.07 dex. Thechemical abundances are consistent with what is expected from theluminosity-metallicity relation. We derive estimates of the electron densitiesand find them to be between ~5 and ~100 cm-3. We find no evidence for anitrogen plateau for objects in this sample with metallicities 0.5 > Zsolar >0.15.

Metal-poor dwarf galaxies in the SIGRID galaxy sample. I. HII region observations and chemical abundances