13 Examined: Dangers of Deer Park Chemical Leaks and How to Protect Your Family from Exposure to Toxic Gases

DEER PARK, Texas (KTRK) — When major leaks or fires occur at oil and gas facilities, complicated chemical terms are often used, but the main concern is simple: Are you and your family safe?

One of the gases that leaked from the Pemex plant in Deer Park on Thursday was hydrogen sulfide.

ORIGINAL REPORT: Two deaths and at least 35 injuries were reported following a chemical release at the Deer Park refinery, officials said

What are the key points you need to know if something like this happens again?

Hydrogen sulfide is often referred to as H2S.

Its nickname is “swamp gas,” and if you’ve smelled it in Pasadena or Deer Park, you know exactly why.

It is notorious for its “rotten egg” smell, but more importantly, the chemical is highly flammable and potentially fatal at high levels of exposure.

Harris County Pollution Control monitors the chemical because it is a byproduct of oil refining. You can see the results here: HCPCS Air Monitoring (arcgis.com), but the data from each test site is not easy to read unless you have a chemistry degree.

Since the county began checking H2S levels at these sites around 6 p.m. Thursday, their meters have shown zero parts per million, meaning there are no signs of H2S.

Raman Krishnamoorti, a professor of petroleum engineering at UH, says if you ever see 300 parts per million, you’re now in a dangerous situation.

According to the Centers for Disease Control, 700 parts per million can cause unconsciousness and death.

Professor Krishnamoorti believes if you smelled the smell of rotting eggs near Dear Park on Thursday, you probably detected around 10 to 20 parts per million, which is little cause for concern.

“At around 20 parts per million you will notice a fairly strong smell of rotten eggs,” Professor Krishnamoorti said. “If they smelled it, it was probably still safe for them. They were probably exposed to it, but not in toxic levels. The problem with hydrogen sulfide is that once the concentration increases, you stop smelling it. And that will become even more dangerous.”

Professor Krishnamoorti says that if you take shelter in a place and no longer smell that terrible stench and start to feel lethargic, you must leave the place where you are and seek medical attention immediately.

The Occupational Safety and Health Administration told 13 Investigates that it has not inspected the Pemex Deer Facility since Shell took over, but the agency is investigating Thursday’s deadly incident.

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READ MORE: Investigators break into unit at center of deadly chemical leak at Deer Park refinery