Polymerization inhibitor compositions

A method comprising

• a) forming a composition comprising about 20 wt % to 50 wt % of one or more nitroxyl compounds, about 20 wt % to 30 wt % water, about 25 wt % to 35 wt % diethylene glycol monobutyl ether, and about 1 wt % to 10 wt % of a hydrocarbon solvent, the hydrocarbon solvent comprising one or more of bis(2-hydroxyethyl) ether, dimethyl benzene-1,2-dicarboxylate, 4-methyl-1,3-dioxolan-2-one, 4-oxa-2,6-heptandiol, 2-(2-hydroxy-propoxy)-propan-1-ol, 2-(2-hydroxy-1-methyl-ethoxy)-propan-1-ol, 2-ethylhexan-1-ol, propane-1,2-diol, and 1-acetoxy-2-butoxyethane;
• b) storing the composition in an enclosed container for a period of about 10 days to 5 years under conditions wherein the composition reaches a temperature between 0° C. and 20° C. at least once during the storage period;
• c) removing the composition from the container by pumping or pouring;
• and
• d) applying the composition to an industrial process stream comprising one or more unsaturated polymerizable compounds.