Which hazard is NOT associated with working in wastewater collection systems?

Working in wastewater collection systems poses several specific hazards, and while high voltage electrical hazards can be present in various settings, they are not directly linked to the unique conditions found within wastewater systems.

Each of the other hazards mentioned—exposure to harmful gases, confined spaces, and potential contact with pathogens—are inherent risks in wastewater collection. For example, workers can be exposed to harmful gases like hydrogen sulfide or methane, which can be lethal in high concentrations, creating a significant risk when working in or around sewer systems. Additionally, confined space entry is a critical concern, as workers often need to enter tanks, pits, or other enclosed environments where they could be at risk of asphyxiation or injury. Furthermore, wastewater often contains pathogens, including bacteria and viruses, which pose a health risk to workers who may come into contact with contaminated surfaces or water.

In summary, while electrical hazards may exist in some contexts related to wastewater management, they are not a central hazard specifically associated with the collection systems themselves, making the choice regarding high voltage electrical hazards the most appropriate answer.