What hazard does hydrogen sulfide pose in wastewater plants and how is it controlled?

• A. It is nonhazardous and requires no controls.
• B. It's toxic and flammable; controlled by gas monitoring, proper ventilation, odor control, and safe working practices.
• C. It only causes pipe corrosion and is controlled by flushing with water.
• D. It enhances odor and is mitigated by adding fragrance.

Answer: (B)