Abstract The hazards associated with the thermal decomposition of chemically incompatible sodium hydride solvent matrices are known, with reports from the 1960s detailing the inherent instability of NaH/dimethyl sulfoxide, NaH/N,N-dimethylformamide, and NaH/N,N-dimethylacetamide mixtures. However, these hazards remain underappreciated and undercommunicated, likely as a consequence of the widespread use of these NaH/solvent matrices in synthetic chemistry. We report herein detailed investigations into the thermal stability of these mixtures and studies of the formation of gaseous products from their thermal decomposition. We expect this contribution to promote awareness of these hazards within the wider scientific community, encourage scientists to identify and pursue safer alternatives, and most importantly, help to prevent incidents associated with these reactive mixtures. | 
