H2S awareness
Hydrogen sulphide is found in sour gas and sour crude across Alberta. It is invisible, heavier than air and can kill in minutes. Work through five short sections to learn how to recognize it, read a gas monitor, escape and respond.
This is an awareness module for learning and orientation. It does not replace certified H2S training required by your employer, such as H2S Alive, or your site's emergency response plan.
Know the gas
Colourless. You cannot see a release or tell where the gas has gone.
Heavier than air. It sinks and pools in ditches, pits, tanks, cellars and low ground.
Smells at very low levels, then deadens your sense of smell at high levels. Never trust your nose.
Flammable range in air. When it burns it forms sulphur dioxide, which is also toxic.
Alberta's 8-hour exposure limit and ceiling limit. A few hundred ppm can knock a person down.
Sour gas wells and pipelines, sour crude tanks, gas plants, sewers, and water with decaying organic matter.
Read the monitor
Everyone on a sour site wears a personal H2S monitor clipped near the breathing zone. Raise the reading to 100 ppm to see how quickly the danger escalates.
Escape: which way do you go?
Move upwind or crosswind, away from the release and toward higher ground. The windsock points the way the wind is blowing, so upwind is the opposite direction. Drag to look around the lease.
Rescue sequence
Most H2S fatalities include someone who ran in to help without breathing protection. Put the response steps in order.
Knowledge check
You've finished H2S awareness
You can recognize H2S hazards, read a personal monitor, pick a safe escape route and follow the rescue sequence. Before working on a sour site, complete the certified training your employer requires.
Content drafted for review by a qualified safety professional. Exposure limits reference the Alberta OHS Code; confirm current values before publishing.