hydrogen sulphide H2S gas is found in Oil and natural gas drilling, wastewater treatment and utility facilities, and sewers, are common locations for the presence of hydrogen sulphide (H2S). When microorganisms break down organic compounds in the absence of oxygen, they release gas. H2S gas, which is colourless, explosive, toxic, and corrosive, emits a rotten egg odour. It is possible that H2S monitoring and early identification could mean the difference between life and death due to its toxicity, which is comparable to that of carbon monoxide
Impact on safety (short-term)
Gas is an unseen danger to the body’s sensors. Hydrogen sulphide poisoning occurs mostly through inhalation. Although some people can detect even low amounts of H2S, long-term exposure to even low levels of H2S has a detrimental effect on the ability to smell (olfactory desensitization). The sense of smell can be completely wiped off if exposed to large gas concentrations. Even while H2S has a distinct smell, it isn’t always a reliable signal of the existence of quantities of the gas.
Additionally, H2S has been shown to irritate mucosal membranes and the respiratory tract. Short-term or acute exposure symptoms may include headaches, nausea, convulsions, and eye and skin irritation. After exposure, acute and severe damage to the central nervous system might occur. Only a few breaths are needed to induce unconsciousness, coma, respiratory paralysis, seizures, and even death at high concentrations.
Impact on health (long-term)
Even after being rendered unconscious by the effects of H2S gas, those who have been exposed long enough may still suffer from headaches, diminished concentration, and impaired motor skills.
Up to 72 hours after being removed from the hazardous area, symptoms of pulmonary consequences from H2S gas exposure may not become apparent.
An accumulation of extra fluid in the lungs known as delayed pulmonary oedema may also occur due to prolonged exposure to high amounts.
If you are repeatedly exposed to low quantities of H2S over an extended period, these symptoms may become more severe.
Skin rashes and eye irritation are possible side effects of prolonged low-level exposure.
Convulsions, coma, brain and heart damage, and even death can result from long-term exposure to high quantities of hydrogen sulphide.
Impact on facilities
H2S gas collects in low-lying parts of poorly ventilated spaces because it is heavier than air.
Sulfuric acid, which can erode metals, can form sour gas (products containing H2S gas) in oil and gas applications when air and moisture are present.
Premature failure of facility equipment, including the internal surfaces of various components, is possible due to lower durability and impact strength.
Detection of H2S gas
As a fast-acting toxin, hydrogen sulphide affects several systems in the body. For early detection and alerting, wearable gas sensors are essential, as the human body does not provide a reliable signal of gas concentrations. Workers exposed to H2S gas should be immediately alerted using gas detectors such as the Blackline G7 wireless gas detector. When working in areas where hydrogen sulphide (H2S) is possible, having a device with a quick response time and a durable build is essential. When it comes to high amounts of hydrogen sulphide (H2S), connected personal monitoring equipment is essential.
When it comes to H2S gas, the following are the OSHA-defined “permissible exposure limits” or “PELs.”
• 20 parts per million (ppm) is the industry standard.
• 50 parts per million (ppm) is the maximum allowable concentration in the general industry (up to 10 minutes if no other exposure during shift)
Only ten ppm are allowed in the 8-hour construction period;
• Shipyard 8-hour limit: 10 ppm
Treatment
Toxic H2S gas should be avoided at all costs by anyone who has been exposed to it. Rescuers must exercise extreme caution when approaching victims who cannot flee on their own for fear of being exposed to H2S. A safety line and respiratory protection are recommended when entering an H2S environment due to the gas’s rapid toxicity. H2S gas poisoning has no known cure. However, the symptoms and adverse effects can be treated or managed. Hospitalization may be required in the most extreme of circumstances.
Any unusual symptoms or side effects should be reported to your doctor immediately, according to the Agency for Toxic Substances and Disease Registry (ATSDR):
• Shortness of breath, wheezing, and difficulty breathing
• Pain or tightness in the upper chest.
• Nausea and diarrhoea
• Headache¬
Intense pain, swelling, and discharge from a burn wound
Maintaining vigilance and avoiding complacency in your safety programme is critical. Calibration and bump testing of gas detecting devices are essential.
Additional resources:
· OSHA: Symptoms of hydrogen sulfide gas exposure
· ATSDR: H2S general information
