H2S is both flammable and toxic!

At 6:45 p.m. on October 28, 2021, an employee was circulating a tank of hydrogen sulfide when a burner box, which was 15 feet away, was turned on and the hydrogen sulfide that was in the atmosphere ignited. The employee was hospitalized to treat second and third-degree burns to his hands and face. 

Source: OSHA.gov