Which dangerous gases might a collection system worker encounter?

A collection system worker may encounter carbon dioxide (CO2) as a dangerous gas due to its potential to create hazardous conditions in confined spaces typically found in wastewater systems. During the decomposition of organic matter in sewage, microorganisms produce carbon dioxide, which can accumulate and displace oxygen in enclosed areas. High concentrations of carbon dioxide can lead to suffocation since it reduces the amount of breathable oxygen available. This risk is particularly pertinent in areas like sewer tunnels and manholes.

While ozone, helium, and ammonia can also pose hazards in certain conditions, carbon dioxide is more commonly associated with the environments related to wastewater collection systems. Ozone is a reactive gas potentially generated in the treatment process, helium is generally non-toxic and doesn't present a significant risk in wastewater situations, and ammonia, while it can be hazardous and is found in wastewater, is less prevalent in the collection system compared to carbon dioxide. Thus, recognizing carbon dioxide as a primary threat is crucial for the safety of collection system workers.