1. Hydrogen Sulfide

2. Hydrogen sulfide (H2S) is an invisible hazard that can be released and produced during industry processes, such as drilling. H2S can also develop naturally in oxygen deficient environments, such as bogs, swamps, polluted water, and manure pits.

3. H2S can collect in: Low-lying areas
Any enclosed facility or piping that contains H2S or H2S-contaminated fluids
Pits
Tanks
Vacuum trucks
Confined spaces

4. At high concentrations, H2S can kill in a single breath.

5. Multiple agencies provide guidelines to help workers avoid H2S exposure, including the American National Standards Institute (ANSI). ANSI recently updated its Z-390 standard for Accepted Practices for Hydrogen Sulfide Safety Training Programs.

6. The 2006 version of the ANSI Z-390 standard was revised to address:
References to obsolete technology
Non-flexible presentation format
Required presentation of material that wasn’t pertinent to most workers
Structure of document
Visitor training
Refresher training
Threshold limit value –time-weighted average (TLV-TWA)

7. The updated 2017 version of the ANSI Z-390 standard now:
References updated technology
Has flexible structure open to partial remote instruction
States that students must be presented with relevant information to ensure their safety
Has an improved structure
States that visitors must receive full worker training program
Requires refresher training annually with full course presentation
Includes the updated American Conference of Governmental Industrial Hygienists (ACGIH) TLV-TWA

8. Companies must use engineering and administrative controls to protect workers from H2S exposure and provide workers with training appropriate to their potential level of exposure to H2S.

9. Some examples of what training should cover include:
Wind direction awareness and routes of egress
What to do in an emergency
Participating in drills

10. Characteristics of H2S include:
H2S goes by many names, including The Silent Killer, rotten egg gas, swamp gas, and sour gas.
Characteristics of H2S include:
Highly toxic, colorless gas
Extremely flammable, may ignite at high temperatures
Extremely explosive, containers of H2S may explode if exposed to fire or handled carelessly

11. You can only smell low concentrations of H2S
You can only smell low concentrations of H2S. At high concentrations, H2S impairs and eventually wipes out your sense of smell. Do not use your nose to detect H2S.

12. You can be exposed to H2S through: Inhalation is your main concern.
Skin contact
Inhalation is your
main concern.

13. Symptoms of H2S exposure include:
Acute Toxicity
Chronic Toxicity
Loss of sense of smell
Excitement or giddiness
Eye irritation
Coughing and sneezing
Headaches
Nausea
Respiratory tract irritation
Diarrhea
Corneal blistering, pitting, and opacity
Pulmonary edema
Loss of appetite
Sleep disturbances

14. The industry accepted exposure level for H2S is 10 ppm:
Check with your company for its accepted exposure level

15. If the H2S concentration may exceed 10 ppm, you need to wear a personal monitor:
Position the monitor as close to your mouth and nose as possible to measure air from the breathing zone
If your monitor goes off, leave the area immediately

16. Wind conditions tell you which way H2S will spread:
Check the windsock or streamer regularly and any time you are unsure which way the wind is blowing
Stay on the upwind side
Make sure you are not downwind of an H2S source
Always move crosswind and then upwind to get away from an H2S source

17. ANSI and the American Petroleum Institute (API) recommend wearing one of the following respirators when you work in environments with more than 10 ppm H2S:
Positive-pressure full-facepiece hoseline/airline supplied-air respirator (SAR) and carry an escape pack
Positive-pressure self-contained breathing apparatus (SCBA)

18. H2S is a deadly hazard that can kill you in a single breath
H2S is a deadly hazard that can kill you in a single breath. Know your role in your company’s H2S contingency plan and participate in drills.

19. Do not rely on your sense of smell to detect the presence of H2S
Do not rely on your sense of smell to detect the presence of H2S. Always wear a personal monitor when working in potential H2S environments. If your monitor goes off, leave the area immediately.