Working in close proximity to hazardous chemicals is a fact of life for many people, and no matter what the circumstance it is always important for individuals to be educated about the potential risks those materials present. It’s a common misconception that the only employments that present regular or real danger are those that involve direct contact with hazardous material, as even brief, irregular, or incidental contact with some chemicals can prove lethal. Because of the potential risks involved with even the most indirect contact, thorough and regular training is important. In the Canadian petroleum industry, H2S Alive is a safety course that is mandatory for all workers that may come into contact with the particularly dangerous hydrogen sulfide gas. Throughout the history of the global petroleum trade, enough incidents have been recorded involving hydrogen sulfide that the safety course is required for all petroleum workers at risk for contact, no matter how fleeting it may be
The Dangers of Hydrogen Sulfide
Hydrogen sulfide gas, also known by its chemical compound formula “H2S,” is a fairly common substance that occurs regularly in nature, as well as in the human body in small quantities. In nature H2S can be found in sewers and swamps, where it is produced as a result of anaerobic digestion (the breakdown of organic matter by bacteria in the absence of oxygen), as well as in volcanic gases. Because of its presence in volcanic gas, H2S can often be found in trace amounts in underground aquifers, natural gas deposits, and in crude petroleum. In the human body the origins of the gas are far more complex, but the basic fact is that in small amounts it serves a few important roles, one of which is helping with memory retention in the brain.
Unfortunately the fact that H2S occurs naturally in the body can lead some people to underestimate how dangerous the gas can be in just about every other circumstance. The amounts found in the body are extremely small, and when respired in larger quantities H2S is a broad-spectrum poison; it has numerous adverse effects on multiple parts of the body. Its toxicity can be accurately compared to that of carbon monoxide or cyanide. One of the most lethal side-effects of H2S respiration is at the cellular level, where it forms a complex bond with iron and inhibits cellular respiration. There is no “magic” number representing a lethal dose, as everyone’s physiological characteristics will react to the gas differently, but the average threshold level is thought to be between 300-500 parts per million.
In small enough quantities the human body produces an enzyme that is capable of neutralizing H2S gas, but between that miniscule dosage and the 300-500 ppm window mentioned above the gas has other negative effects. Respiration at these lower levels can cause eye irritation, sore throat, nausea, and even the numbness of a person’s sense of smell (this particular side-effect can make detection of the gas through scent difficult after prolonged exposure). When non-lethal dosages have been respired regularly over a long period of time, the effects can include lapses in memory, loss of appetite, dizziness, and chronic headaches.
H2S and the Petroleum Industry
As previously mentioned, hydrogen sulfide gas is commonly found in natural gas and crude oil deposits, due to its presence in volcanic gases. Its presence in both of these potential fuel sources makes it a regular fixture in the lives of all petroleum industry workers, and even more so because the gas is one of the chemicals that must be separated from the fuels during the refining process. Both natural gas and crude petroleum containing H2S are referred to as “sour” (sour gas and sour crude respectively), and there are regulations from region to region governing the amount of sulfide that can be contained in them before they can be refined for use as fuel.
Aside from the health risks it poses to workers from accidental respiration, hydrogen sulfide is also extremely flammable. Given the high levels of volatility of the other materials worked with in the industry (i.e. crude oil and natural gas), a highly flammable gas represents an added danger as well.
H2S Alive Training
Because of the multiple risks that hydrogen sulfide gas represent to workers of the petroleum industry, the required training course H2S Alive covers everything from understanding the basic properties of hydrogen sulfide gas, to responding and ultimately resolving any potential situations that could develop from an accident or other potentially dangerous incident. In the Canadian petroleum industry the course is not only required, but it is only valid for up to three years before individuals must take the course again.
There are numerous organizations out there offering H2S Alive training courses, and as long as they offer industry certified training than it is simply a matter of personal preference in locating the organization that offers a program suiting an individual’s needs. Despite the minor differences in structure and content, every H2S Alive course should cover these fundamentals:
- Basic Understanding & Detection of H2S Gas
- Locating & Using the Proper Respiratory Safety Equipment
- Rescue Best Practices (including carries, C.P.R, etc.)
- Practical Application of Skills & Relevant Case Studies
The time it takes to cover the above material and all of their constituent parts varies slightly from organization to organization, but in general it should take about 8 hours to complete. Courses should include a combination of book work, examinations, as well as physical practice of relevant rescue techniques and use of safety equipment. For anyone looking to find and complete an H2S Alive course for their employment, a simple internet search should return a variety of certified organizations in their area.