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How to Check for Hydrogen Sulfide

Hydrogen sulfide, or H2S, is a colorless, flammable, toxic gas found in hot springs, volcanoes, natural gas wells, mines, sewers, paper mills and other manufacturing plants. A few breaths of air containing hydrogen sulfide at a concentration of 500 parts per million, or ppm, can cause death. At a concentration of 10 ppm, hydrogen sulfide exposure causes irritation of the eyes, nose and throat. At a concentration of 10 ppm to 50 ppm, exposure causes dizziness, headache, nausea, vomiting and breathing difficulty. Hydrogen sulfide gas has a very distinct odor at certain concentrations, and you can use a gas monitor to detect hydrogen sulfide.

Things You'll Need

Gas monitor

Instructions

Smell
- 1
  Inhale normally and take note of any odor present. If you smell an odor like rotten eggs, there may be hydrogen sulfide gas present in the air at a concentration of up to 30 ppm. At a concentration of 30 ppm to 100 ppm, hydrogen sulfide gas has a sickeningly sweet odor.
- 2
  Leave the area immediately if you smell these odors or experience any of the symptoms of hydrogen sulfide gas exposure.
- 3
  Wear protective gear and communication equipment if you return to the area. Ventilate the area containing the hydrogen sulfide gas if possible.
Gas Monitor
- 4
  Turn on the gas monitor by pressing the "On/Off" button. The pilot light should light up indicating that the device has power, and the display screen will turn on.
- 5
  Verify air is entering the device. Block the tube that air enters through with your thumb. The reading on the display screen should indicate reduced airflow. Remove your thumb.
- 6
  Press the "Menu" button and select hydrogen sulfide gas to set your multiple gas monitor to detect hydrogen sulfide gas. Skip this step if you are using a single gas monitor designed to detect hydrogen sulfide gas.
- 7
  Hold the monitor in an area that you wish to test for hydrogen sulfide gas. Read the display screen to check the concentration of hydrogen sulfide gas present.
- 8
  Leave the area immediately if any of the alarms trigger. A gas monitor usually has three alarms. The screen will indicate high hydrogen sulfide gas concentration and an audio alarm will sound. It also has a vibrating alarm for use in high noise areas.

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