Protecting Employees Against Hydrogen Sulfide Worksite Hazards

Chris Detillier


June 11, 2020

June is National Safety Month, which the National Safety Council says "focuses on saving lives and preventing injuries, from the workplace to anyplace." Organizations can observe the occasion by addressing both everyday safety issues, as well as lesser-known dangers. Although a majority of safety operations specialists and administrators stay up to date with federal, state and regional regulations necessary to keep their workforces safe, many are unaware of the protocols that pertain to hydrogen sulfide, otherwise known as H2S or sour gas. Unfortunately, this oversight becomes particularly hazardous for those working in high-risk environments that can produce H2S, which is the second most common cause of workplace gas inhalation fatalities after carbon monoxide.

Called the “silent killer,” the primary method of exposure to the colorless, flammable gas is through inhalation, and unfortunately, workers can only smell its “rotten egg” odor when lower concentrations exist. According to OSHA, H2S is produced naturally from decaying organic matter, and mostly emitted as a by-product of numerous industrial processes such as:

  • Sewage and wastewater treatment systems: Anywhere organic material, including human or animal waste, is left to break down
  • Restoration, renovation and demolition: Excavation work in landfills or swamps
  • Mining: Mineral rock containing hydrogen sulfide found in tunnels
  • Oil and Gas: Drilling can release hydrogen sulfide dissolved in oil and gas
  • Additional environments: Pulp and paper, hot asphalt production, manure pits, food processing, and agriculture silos are also common sources for H2S

Often collecting in low-lying and enclosed, poorly ventilated spaces, the gas can easily and quickly overpower workers surveying and performing tasks in basements, caves, tunnels, manholes, landfills, underground utility vaults, marshy areas, and sewer lines, as well as those working with asphalt. Workers who experience prolonged exposure to H2S may notice physical symptoms, including, but not limited to: 

  • Nausea, tearing of the eyes, headaches, loss of sleep
  • Possible fatigue, loss of appetite, irritability, poor memory, dizziness
  • Slight conjunctivitis and respiratory tract irritation, loss of smell/olfactory paralysis, altered breathing
  • Collapsing, serious eye damage, and death within 30 to 60 minutes
  • Rapid unconsciousness within one or two breaths and death within minutes for high concentration exposures

Adding to the threat, some companies and contractors prioritize productivity and job completion rates over comprehensive safety practices. Without the training and insight needed to navigate worst-case scenarios associated with exposure, this can put workers at high risk. Proper worker safety training and risk management strategies can prevent injury, illness and workplace deaths related to the toxic gas. By implementing annual retraining, companies can ensure those working or visiting a location where H2S could be present have the knowledge and expertise needed to recognize, avoid and contain it.

To provide best-in-class training, companies should choose a well-established and industry-recognized training program. Learning how to identify H2S and its characteristics, understand the concentration levels and proper reactions, use monitoring and personal protection devices, recognize the physical signs and symptoms of exposure, and properly aid and treat others exposed to this deadly gas are all mission-critical.

In addition to making employee safety training the cornerstone of their corporate safety programs, there are three other proactive measures safety administrators can take to protect workers:

  1. Frequent communications about safety.

How companies introduce and explain a new program or policy is key to its acceptance and success. Review updated safety regulations with workers before launching any new program, and be sure communication is ongoing. This can include meetings, lunches, awards, posters or even merchandise to create momentum and awareness around a safety campaign.

  1. Establish and communicate clear expectations and goals of acceptable safety performance.

When employees know what they must accomplish and how it relates to an overall goal, they will feel more empowered to do what it takes to complete their responsibilities. Also, consider setting SMART goals (Specific, Measurable, Achievable, Relevant and Time-bound) so each employee will know their part in achieving success.

  1. Provide top-of-the-line monitoring and protection equipment.

Choose the H2S monitoring and personal protection equipment and devices that best suit the company’s needs. Risk decreases significantly if workers are highly trained and supplied with proper monitoring equipment, and have detailed safety and health procedures to follow when working in confined spaces and H2S-prone environments.

Not only is it simple economics, but maintaining the well-being of a workforce is also a moral obligation. Establishing sound safety programs and training courses that meet requirements set by the ANSI/ASSE Z-390.1 Rev. 2017 (Accepted Practices for Hydrogen Sulfide Training Programs) standard can help ensure that workers are safe on the job and prepared to confront the dangers of H2S.

Chris Detillier, COSS/COSM, is the senior HSE advisor at Veriforce. In his role, Chris is a master trainer and also serves as a lead subject matter expert in industry-specific content for the training product development group. Detillier holds degrees in Science Petroleum Technology and Science Safety Technology from Nicholls State University.