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  • June 05, 2026
June 5, 2026
Quicktakes: Did You Know? English/Español

Did You Know?

Hydrogen sulfide (also known as H2S and sewer gas) is a colorless gas known for its powerful "rotten egg" odor. It is extremely flammable and highly toxic. Used or produced in a number of industries, hydrogen sulfide also occurs naturally in sewers, manure pits, well water, and oil and gas wells. Because it is heavier than air, it can collect in low-lying or enclosed spaces, such as manholes, sewers, and underground telephone vaults. Even low levels can cause health hazards and make working in confined spaces potentially very dangerous. Symptoms can range from headaches or eye irritation, to unconsciousness and death. It can also cause an explosion if exposed to a spark, flame, or other ignition source.

To protect workers:

  • Evaluate exposure to know whether H2S gas is present and at what levels.
  • Eliminate the source of hydrogen sulfide whenever possible.
  • If the source cannot be eliminated, control exposures through engineering controls (first line of defense) or administrative controls and safe work practices to reduce exposures to safe levels.
  • Use personal protective equipment if engineering controls and work practices alone cannot reduce hydrogen sulfide to safe levels.

Visit our website for more information on how hydrogen sulfide can affect your health, and how to prevent harmful exposures.

¿Sabías?

El sulfuro de hidrógeno (también conocido como H2S y gas de alcantarilla) es un gas incoloro conocido por su potente olor a “huevo podrido”. Es extremadamente inflamable y altamente tóxico. Utilizado o producido en diversas industrias, el sulfuro de hidrógeno también se encuentra de forma natural en alcantarillas, fosas de estiércol, agua de pozo y pozos de petróleo y gas. Debido a que es más pesado que el aire, puede acumularse en áreas bajas o espacios cerrados, como pozos de registro, alcantarillas y cámaras subterráneas de telefonía. Incluso niveles bajos pueden causar riesgos para la salud y hacer que el trabajo en espacios confinados sea potencialmente muy peligroso. Los síntomas pueden variar desde dolores de cabeza o irritación ocular hasta la pérdida del conocimiento y la muerte. También puede causar una explosión si se expone a una chispa, una llama u otra fuente de ignición.

Para proteger a los trabajadores:

  • Evalúe la exposición para saber si el gas H2S está presente y en qué niveles.
  • Elimine la fuente de sulfuro de hidrógeno siempre que sea posible.
  • Si la fuente no puede eliminarse, use controles de ingeniería (primera línea de defensa) o controles administrativos y prácticas seguras de trabajo para reducir las exposiciones a niveles seguros.
  • Use equipo de protección personal si los controles de ingeniería y las prácticas de trabajo por sí solos no pueden reducir el sulfuro de hidrógeno a niveles seguros.

Visite nuestro sitio web para obtener más información sobre cómo el sulfuro de hidrógeno puede afectar su salud y cómo prevenir exposiciones perjudiciales.

Evaluate exposure to know whether hydrogen sulfide gas is present and at what levels.


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