Hydrogen sulfide (H 2 S) emission from liquid manure in the process preceding field application is an important issue in fertigation systems. Given that H 2 S poses a significant health risk, it is important to determine the effects of different handling parameters on H 2 S emissions to prevent health risks to farmers. In this study, the effects of total solids (TS; 3, 5, 7, 9, and 11%) and mixing speed (100, 200, 300, and 400 rpm), duration (5, 15, 30, and 60 min), and frequency (one, two, three, and four times a day) on H 2 S emissions from two different dairy manures were investigated. The results indicate that the quantity of sulfur-containing substrate intake determines the potential of dairy manure to emit H 2 S because manure from cows fed with concentrate-based feed generates higher amounts of H 2 S than manure from cows fed with forage-based feed. The H 2 S concentration increased with TS concentration and reached a maximum of 1133 ppm at a TS of 9%; thereafter, it decreased with further increases in TS concentration. H 2 S emission increased with mixing speed with a peak concentration of 3996 ppm at 400 rpm. A similar trend was observed for mixing duration. However, there were no significant differences between the amounts H 2 S emitted at different frequencies of mixing (P > 0.05). The results indicate that mixing speed, duration, and TS are the major determinants of the quantity of H 2 S emitted from dairy manure. Therefore, to prevent health risks associated with H 2 S emission from dairy manure, it is recommended that the mixing speed and duration should be kept as low as possible, while a TS concentration of above 9% should be applied during the fertigation of dairy manure.