Best H2S Monitor for Manure Pit Safety (2024 update)

H2S Monitor, Hydrogen Sulfide Detector -

Best H2S Monitor for Manure Pit Safety (2024 update)

H2S Monitors are important tools in agriculture and farming in particular around manure pits on livestock farms which harbor hydrogen sulfide gas. This byproduct of decomposing manure is both highly toxic and difficult to detect, making dedicated H2S monitoring absolutely vital. Farms must employ robust hydrogen sulfide detectors to continuously sample pit atmospheres and trigger alerts before concentrations reach hazardous levels. Tragically, numerous past incidents of H2S poisoning deaths underscore the criticality of these life-saving detection devices. From agriculture to refining, mining, and various industrial settings, hydrogen sulfide gas detectors provide indispensable real-time exposure data and early warning against this insidious asphyxiant. Prioritize comprehensive H2S monitoring to prevent needless loss of life.



  • An H2S monitor is an inexpensive piece of detecting equipment costing less than $100.
  • Hydrogen sulfide is dangerous and life-threatening gas, so using a monitor can save a life.
  • Hydrogen sulfide is an aromatic gas, but at high concentrations, can inundate and cause fast unconsciousness.
  • The sensors that hydrogen sulfide detectors use often have to be replaced every 24-36 months.
  • Manure pits are dangerous as when mixed can emit larger amounts of H2S gas that without warning, can inundate farmers.

What is the Best H2S Monitor for Manure Pits?

The top hydrogen sulfide gas detectors for farms and manure gas personal protection includes the following:

Why Are Manure Pits Dangerous?

Manure pits are dangerous because they facilitate the decomposition of fecal waste and other waste from animals to produce dangerous gaseous compounds.

Such compounds may include methane, carbon dioxide, ammonia, and hydrogen sulfide, each coming with their own negative health consequences.

What Kind of Gas Does Manure Give Off?

Manure produces a number of gases. Hydrogen sulfide, methane, and carbon dioxide are just three examples of gases produced during decomposition. Each one poses its own unique risks to human and animal health, but hydrogen sulfide is often regarded as the most dangerous.

What is Hydrogen Sulfide?

Hydrogen sulfide is a colorless gas that is commonly said to smell like rotten eggs. It can be referred to by other names, as well, including the following:

  • H2S
  • Sewer Gas 
  • Swamp Gas
  • And more

It is a naturally occurring gas in a number of locations including the following:

  • Sewers
  • Manure pits
  • Oil wells
  • Gas wells
manure pit gas detector

What is a H2S Monitor?

An H2S gas detector is a monitoring device used to detect the presence of hydrogen sulfide gas in a given environment. It is capable of measuring the concentration of the hydrogen sulfide gas in a manure pit.

Hydrogen sulfide detectors go by many names. Some examples include H2S monitor, hydrogen sulfide meter, H2S gas detector, and hydrogen sulfide gas detector.

What Are Symptoms of Hydrogen Sulfide?

Potential exposure to hydrogen (H2S gas) can cause a number of symptoms ranging in severity including the following:

  • Eye irritation
  • Cough
  • Shortness of breath
  • Nausea
  • Headache
  • Delirium
  • Loss of consciousness
  • Death

The symptoms caused by hydrogen sulfide poisoning are serious. This highlights the importance of proper gas monitoring in manure pits and other farm operations where the decomposition of animal waste may take place.

gas inspection

Is Hydrogen Sulfide Dangerous?

Yes it is.

H2S gas is dangerous to humans and animals. 

Humans will be negatively affected by H2S gas if they breath it in air with a plethora of various symptoms.

OSHA notes that hydrogen sulfide gas is both flammable and explosive. As it burns, it also has the capacity to release toxic compounds into the air. Additionally, it can cause a number of health problems in both humans and animals, such as the symptoms described previously.

What Does Hydrogen Sulfide Do To Animals?

Hydrogen sulfide is potentially fatal to animals, especially farm animals such as cattle.

In fact, in 1997, upon exposure to hydrogen sulfide, 26 cows died in a matter of minutes. 7 more were affected greatly for several hours, appearing blind and staggering, before recovering. An additional 2 cows were euthanized in order to diagnose the tragic cause of the cattle deaths as hydrogen sulfide poisoning.

The continuous exposure of H2S gas to livestock also affects their productivity, yield and wellness, hence the importance of H2S gas monitoring.

How Do You Make Hydrogen Sulfide Gas?

In swine barns and manure pits, hydrogen sulfide gas is produced when manure decomposes in the absence of oxygen gas.

The sulfur is introduced to the decomposing manure through both feces and urine during this process, as the Ministry of Agriculture, Food, and Rural Affairs remarks. As the hydrogen sulfide gas continues to be produced, it remains bonded to the manure particles and accumulates to large quantities in a relatively short period of time.

How Do I Select an H2S Monitor for Manure Pits?

For manure pits, you need:

  • a H2S monitor that can be clipped to your man, on your belt, jacket or jeans
  • a H2S meter with alarms having LED, BUZZER and VIBRATION
  • a H2S meter that runs on a battery for at least 24 hours to last the days work
  • depending on the weather, you may desire for it to be waterproof and having a IP rating of at least IP65 but better for it to be rated at IP67
  • small and compact so when wearing the unit it does not interfere with your work

How Does a Hydrogen Sulfide Detector Work?

A hydrogen sulfide gas detector uses electrochemical sensors in order to monitor the presence of of hydrogen sulfide gas. They use either ppm or ppb for their units of hydrogen sulfide quantity. The sensors are alerted of the presence of hydrogen sulfide gas when an electrochemical reaction occurs with the introduction of the gas.

Have There Been Any Deaths from Hydrogen Sulfide in Manure Pits?


Hydrogen sulfide has taken the lives of a number of animals and workers over the years.

In 1992, two men died in a manure pit in Minnesota, one dying in a rescue attempt for the first man.
In 2016, a man died in a manure pit in Wisconsin along with thirteen cattle and three more cattle who were later euthanized as a result of the effects of the poisoning.
In 2021, three men died after being in a manure pit in Ohio.

    Is Hydrogen Sulfide Gas a Problem in a Swine or Hog Farm?

    Yes it is.

    Hydrogen sulfide gas is a major problem in swine and hog farms because of its production in manure pits. In fact, hydrogen sulfide gas is frequently believed to be the most dangerous gas produced in manure pits. This gas is dangerous to both swine and humans, and has caused death in both groups in the past.

     manure pits

    Is the Smell of Manure Harmful?

    The smell of manure may or may not be harmful.

    If a rotten egg smell is detected, it has the potential to be harmful because of the presence of hydrogen sulfide. With that said, hydrogen sulfide has a very low odor threshold, so it might be smelled at levels lower than it can harm humans.

    Regardless, the utmost care should be taken when working in or around manure pits, especially when hydrogen sulfide can be smelled. This gas is dangerous and has taken lives in the past.

    Where Is a H2S Monitor Used?

    Other than manure pit personal protection, H2S monitors and detectors are used in:

      • Sewer & wastewater
      • Agricultural silos & pits
      • Textile and clothing manufacturing
      • Pulp & paper processing
      • Food processing

    How is Hydrogen Sulfide Removed from the Air?

    There are several mechanisms used to remove hydrogen sulfide gas from the air, and more mechanisms are currently being investigated by researchers. One group of researchers evaluated the effectiveness of using cellular concrete waste as a packing material to remove hydrogen sulfide from the air and found that it was effective.

    How Does the Body Get Rid of Hydrogen Sulfide?

    Hydrogen sulfide is removed from the body by metabolism in the liver. This takes place after the body and its blood supply naturally carries the molecules of hydrogen sulfide to the liver where specialized cells clean the solution brought to them and filter out any waste, hydrogen sulfide included.

    How Long Does Hydrogen Sulfide Stay in Your System?

    Hydrogen sulfide does not actually remain in or accumulate in the system. Instead, it is metabolized rapidly in the liver and is excreted within the urine.

    What are the Long Term Effects of Hydrogen Sulfide?

    Repeated exposure to hydrogen sulfide may cause a number of health problems, especially when exposed to different levels of hydrogen sulfide. Such health effects may include the following:

    • Low blood pressure
    • Loss of appetite
    • Weight loss
    • Headache
    • Rash
    • Irritation of the eyes
    • Convulsions
    • Coma
    • Brain damage
    • Heart damage
    • Death


    Which Gases Are Concerns for Swine Welfare?

    Iowa State University reports five primary gases as being prominent in swine environments, including manure pits. They include the following:

    • Ammonia
    • Carbon dioxide
    • Carbon monoxide
    • Hydrogen sulfide
    • Methane

    All five of the above gases pose a potential threat to both swine welfare and human welfare as well. Thus, proper care must be taken to ensure that workers and swine are both safe from potential adverse effects of the gases. If proper care is not taken, farm owners and workers may lose not only swine, but human lives as well.

    At What Level Can You Smell Hydrogen Sulfide?

    Hydrogen sulfide gas can be smelled at relatively low levels. In fact, the odor of the gas can be identified at concentrations lower than that which is able to cause serious, adverse health reactions.

    The lower detection limit for humans for H2S gas is 0.00041ppm.

    What is H2S Olfactory Fatigue?

    Olfactory fatigue, also known as odor fatigue or olfactory adaptation, is a phenomenon where the sense of smell becomes less sensitive to a particular odor over time. This occurs when the olfactory receptors in the nose become desensitized to a specific odor due to prolonged or repeated exposure.

    In the case of smelly gases such as hydrogen sulfide (H2S) gas, olfactory fatigue can occur when a person is exposed to the gas for an extended period of time. At first, the person may be able to detect the strong, unpleasant odor of the gas, but over time, their sense of smell may become less sensitive to it, and they may no longer be able to detect the odor as strongly. This can be dangerous, as it may lead to a false sense of security and prevent the person from realizing that they are still being exposed to the gas.

    Final Words

    That rotten egg smell signals a lethal threat - hydrogen sulfide gas. This invisible asphyxiant endangers humans and livestock alike when released from decomposing manure pits. Affordable personal H2S detectors are a must for anyone working near these hazardous environments. Too many tragic deaths have resulted from inadequate monitoring and symptom recognition around manure pits' fugitive H2S releases. From dizziness and respiratory distress to unconsciousness, missed signs can prove quickly fatal without intervention. Dedicated gas detection provides critical real-time exposure data to trigger evacuation before concentrations overwhelm. On farms, refineries, or any H2S-risk facility, prioritize comprehensive monitoring with personal H2S alarms to prevent needless poisoning incidents.

      About the Author

      Dr. Kos Galatsis ("Dr.Koz") is the President of FORENSICS DETECTORS, where the company operates from the scenic Palos Verdes Peninsula in Los Angeles, California. He is a subject matter expert on gas sensor technology, gas detectors, gas meters, and gas analyzers. He has been designing, building, manufacturing and testing toxic gas detection systems for over 20 years.

      gas detector expert

      Every day is a blessing for Dr. Koz. He loves to help customers solve their unique problems. Dr. Koz also loves spending time with his wife and his three children going to the beach, grilling burgers, and enjoying the outdoors.

      Read more about Forensics Detectors here.

      Phone: +1 424-341-3886