Weekly Safety Meeting – Hydrogen Sulfide

Hydrogen Sulfide

Hydrogen sulfide is a colorless, flammable, extremely hazardous gas with a “rotten egg” smell. It occurs naturally in crude petroleum and natural gas and can be produced by the breakdown of organic matter and human/animal wastes (i.e., sewage).

It is heavier than air and can collect in low-lying and enclosed, poorly ventilated areas such as basements, manholes, sewer lines, and underground telephone/electrical vaults.

It is also used or is a by-product in many industrial processes such as:

• Petroleum production and refining;

• Sewer and wastewater treatment;

• Agricultural silos and pits;

• Textile manufacturing;

• Pulp and paper processing;

• Food processing;

• Hot asphalt paving; and

• Mining

Detection by smell:

• It can be smelled at low levels, but with continuous low-level exposure or at higher concentrations you lose your ability to smell the gas even though it is still present.

• At high concentrations your ability to smell the gas can be lost instantly.

• DO NOT depend on your sense of smell for indicating the continuing presence of this gas or for warning of hazardous concentrations.

Health effects:

• Health effects vary with how long, and at what level, you are exposed. Asthmatics may be at greater risk.

• Low concentrations – irritation of eyes, nose, throat, or respiratory system; effects can be delayed.

• Moderate concentrations – more severe eye and respiratory effects, headache, dizziness, nausea, coughing, vomiting and difficulty breathing.

• High concentrations – shock, convulsions, unable to breathe, coma, death; effects can be extremely rapid (within a few breaths).

• The detector should be worn below the neck.

• A single alarm activation will require that all employees evacuate the area.