Best Chlorine Dioxide Gas Detector (2024 update)

Chlorine Dioxide Detector, ClO2 Detector -

Best Chlorine Dioxide Gas Detector (2024 update)

Chlorine dioxide gas, known for its antimicrobial properties, is widely used in industrial applications for sanitizing and disinfecting products, surfaces, and areas, including drinking water. However, chlorine dioxide gas detectors are crucial when working with chlorine dioxide, as improper monitoring can pose significant hazards to human health. Inhalation of the gas can cause irritation, while its reaction with other substances may lead to fire or explosion. To minimize the risks associated with chlorine dioxide gas, a chlorine dioxide gas detector should be employed to continuously monitor the concentration of the gas in a given location. These detectors provide real-time measurements, enabling swift action to be taken when chlorine dioxide levels exceed safe thresholds, thereby protecting the health and safety of individuals in the vicinity.



  • Chlorine dioxide is a highly reactive gas
  • A Chlorine dioxide gas detector is used to detect the amount of chlorine dioxide gas present in an area where the gas is readily employed for disinfection purposes
  • Chlorine dioxide gas detectors may be useful in healthcare settings, wastewater treatment, food and beverage manufacturing, swimming pool cleaning, and more
  • Chlorine dioxide gas detectors vary in a large price range from $100s to $10,000s, depending on the sensitivity and quality of the device
  • ClO2 is tricky to calibrate, it must be generated or another gas can be used as an alias gas calibrator.

Best Chlorine Dioxide Gas Detector?

Chlorine dioxide detectors can be a worthwhile purchase for those needing to test for chlorine dioxide gas. They can be purchased from several online retailers. Some examples of effective devices include:

How is Chlorine Dioxide Gas Detected?

Chlorine dioxide gas can be detected using a chlorine dioxide gas detector. Although it is colored and has an odor, only a chorine dioxide gas detector can accurately monitor the concentration of chlorine dioxide gas. More specifically, the detector should use ppm or ppb monitoring equipment instead of explosive capacity LEL monitoring equipment.

Who Uses Chlorine Dioxide Gas?

Chlorine dioxide gas is used in various industries and applications due to its potent disinfectant and oxidizing properties. Some of the primary users and uses include:

  1. Water Treatment: It's extensively used for water purification and disinfection. Chlorine dioxide is effective in eliminating bacteria, viruses, and some types of parasites that are commonly found in water. It's used both in municipal water treatment facilities and in industrial water treatment processes.

  2. Pulp and Paper Industry: This industry uses chlorine dioxide for bleaching wood pulp in the production of high-quality, white paper products. It's preferred over chlorine because it produces fewer chlorinated byproducts, which are harmful to the environment.

  3. Food and Beverage Industry: Chlorine dioxide is used as a disinfectant in the food industry. It's employed for sanitizing equipment, containers, and surfaces, and also in water used in food processing to eliminate microbial contamination.

  4. Medical and Laboratory Settings: It's used for disinfecting and sterilizing medical equipment and facilities. In laboratories, chlorine dioxide gas can be used to decontaminate surfaces and equipment, especially in biosafety labs or areas where there's a risk of microbial contamination.

  5. Cooling Towers and HVAC Systems: Chlorine dioxide is effective in controlling biofilm, algae, and other microbial growth in cooling towers and HVAC systems, thus improving efficiency and preventing the spread of airborne pathogens.

  6. Oil and Gas Industry: Used for water disinfection processes in the oil and gas industry, particularly in hydraulic fracturing (fracking) where large volumes of water are involved.

  7. Agriculture: Employed for disinfecting water used in agricultural processes and for sanitizing tools and equipment to prevent the spread of plant diseases.

  8. Odor Control: Chlorine dioxide gas is effective in eliminating odors caused by bacteria, mold, smoke, and other organic substances, and is used in various commercial and industrial settings for this purpose.

What is in a Chlorine Dioxide Gas Sensor?

Like most detectors, a chlorine dioxide gas detector is composed of several key parts. The ClO2 sensor is critical to detecting the presence of the chlorine dioxide gas. These are typically chlorine dioxide gas sensor using electrochemical gas sensing technology. The ClO2 gas causes a chemical reaction in electrochemical sensors, resulting in a current that is directly proportional to the gas concentration present. The sensors consume extremely little power and respond well to a variety of gas concentrations across a wide range of environmental conditions.

Chlorine Dioxide Gas Detector

What is Chlorine Dioxide Gas?

Chlorine dioxide gas is denoted by the chemical symbol, ClO2. At room temperature, it appears as a yellow-green gas with a faintly bleach-like odor. It has many important applications, particularly for disinfection.

Is Chlorine Dioxide Gas Hazardous?


Chlorine dioxide can have negative effects on the human body when it is inhaled. Certain symptoms may include:

  • Skin irritation
  • Eye irritation
  • Nose irritation
  • Throat irritation
  • Coughing
  • Wheezing
  • Shortness of breath
  • Pulmonary edema

Chlorine dioxide gas is also highly flammable and highly explosive. It is very reactive, so it is important that it is kept away from chemicals with which it may interact.

What is a Chlorine Dioxide Gas Detector?

A chlorine dioxide gas detector is a monitoring device used to measure the concentration of chlorine dioxide gas present in a air. 

Chlorine dioxide gas detectors come in many different form factors and features.

These devices are often used to confirm a target ClO2 concentration that a saniting technician plans to target. Or the inverse, used to monitor safe levels of ClO2.

Please note that chlorine is not the same as chlorine dioxide. Chlorine gas detectors should not be used to detect the presence of chlorine dioxide gas.

Are there ClO2 sensor interference gases?

Unfortunately, electrochemical sensors are not completely selective, and they respond to other gases present in the environment.

The probable interferences that may be experienced when utilizing the ClO2 Detector are listed below. The table shows the Chlorine Dioxide sensor's relative response to 1 PPM of the listed gas, given as a relative PPM Chlorine Dioxide signal. A chlorine dioxide sensor, for example, would provide a signal equivalent to 1 PPM of chlorine when exposed to a gas sample containing 1 PPM of Cl2. If a mixture of chlorine dioxide and that gas is encountered, a negative sign (-) indicates an interference that could result in low ClO2 values.

Please note, the below values are a rough guide. These ratios can change with sensor manufacturer and sensor range selections.

Chlorine Dioxide Gas Detector

How Can I Calibrate a ClO2 Detector?

Although chlorine dioxide standards are not available for calibration, chlorine standards can be utilized because a chlorine dioxide sensor responds 1:1 to chlorine. This ratio may change slightly with different ClO2 sensor manufacturers and ranges. Established NO2 or Cl2 certified NIST gas bottles can be used as a proxy to calibrate ClO2 sensors.

How Do You Select a Chlorine Dioxide Gas Detector?

Selecting a chlorine dioxide gas detector requires considering several factors of the intended use of the device.

  • What is the measuring range?
  • Are there any other gases in the monitoring area that could skew readings?
  • Has the device been calibrated or will you need to find an organization to calibrate it for you?
  • Will the device be localized to one location or will it move around with users?
  • Does diffusion detection suffice, or is a built in pump and probe required to sample the gas stream?

How is Chlorine Dioxide Gas Used in Sanitization?

Chlorine dioxide gas is frequently used in sanitization and sterilization capacities. Specifically, it is used in healthcare spaces to sterilize medical equipment and laboratory equipment. It can also sterilize rooms and other important spaces and items found in medical settings.

Medical and laboratory equipment, surfaces, spaces, and tools are all sterilized with chlorine dioxide gas. 

Chlorine dioxide may be used to specifically target Legionella bacteria, which may have disastrous impacts on patients who become infected by it.

Chlorine Dioxide Gas Detector

How is Chlorine Dioxide Gas Used in Disinfection?

Chlorine dioxide can be used as a disinfectant or an oxidant. It's a powerful oxidant that can kill dangerous microbes like fungi, bacteria, and viruses. 

Chlorine dioxide can be readily used as a disinfectant.

What is Abatement?

Abatement typically refers to the reduction of something. In the context of chlorine dioxide, abatement may be used to describe the reduction of a given chemical or compound after exposure to chlorine dioxide gas.

How is Chlorine Dioxide Gas Used in Abatement?

Chlorine dioxide gas has been used for abatement in wastewater in the past. It can be useful in this application because of its ability to reduce micropollutants. Typically, it accomplishes this through its strong oxidizing ability.

Who Uses a Chlorine Dioxide Gas Detector?

Chlorine dioxide gas detectors may be used primarily by employees in certain industries. Such industries may include:

  • Personal car product production
  • Oil
  • Gas
  • Food
  • Beverage
  • Municipal

The average person not working in these industries will likely not come into contact with potentially dangerous levels of chlorine dioxide gas and thus would not need to use a chloride dioxide gas detector.

How is Chlorine Dioxide Gas Generated?

Chlorine dioxide gas is typically generated by purposeful actions. It is not found naturally, so must be produced through chemical reactions. 

Specifically, chlorine dioxide gas can be generated when hydrochloric acid or chlorine is reacted with sodium chlorite.

ClO2 generators can be found here.

Chlorine Dioxide Gas Detector

Is Chlorine Dioxide Gas Flammable?


In fact, it is considered extremely flammable and can cause both fires and explosions if it is allowed to react with certain chemicals. Because of this, it is imperative that it is treated with caution and is continually monitored to evaluate how much is in the area at a given time.

How Do You Use a Chlorine Dioxide Gas Detector?

Chlorine dioxide gas detectors can be found in fixed and portable forms. After the correct device has been purchased (based on whether the device will need to move around or stay in one location), it is imperative that it is calibrated. Further, users must be sure to continually check the power supply and ensure that it is still functioning properly.

Can You Detect Chlorine Dioxide Gas By Smell?


Chlorine dioxide can be detected by smell as it does have a strong odor. Its odor threshold is 0.1-0.3 ppm. Yet, the human nose is not capable of accurately determining the concentration of chlorine dioxide gas present, so a chlorine dioxide gas detector is necessary for effective monitoring.

How Is Chlorine Dioxide Gas Stored?

Chloride dioxide gas is typically not sored, but its liquid form is.

Chlorine dioxide is best stored as a liquid at 4 degrees Celsius. It cannot be stored for long because it will dissociate. It is typically not stored as a gas because it can be explosive under pressure.

What is the Biggest Use for Chlorine Dioxide Gas?

Chloride dioxide gas is best known for its antimicrobial uses. Among these include disinfecting drinking water. This use may be most clearly seen within the municipal industry.

What Makes Up a Chlorine Dioxide Gas Detector?

Like most detectors, a chlorine dioxide gas detector is composed of several key parts.

  • The sensor: the sensor is critical to detecting the presence of the chlorine dioxide gas in the first place
  • The output: after the sensor recognizes the presence of the chlorine dioxide gas, it pushes that information to a different component that converts that concentration to a reading interpretable by people
  • The energy supply: the energy supply allows the device to continue working. This can vary depending on if the detector is portable or fixed

Is Chlorine Dioxide Gas the Same as Chlorine Gas?


Chlorine dioxide gas is typically dictated by ClO2 while chlorine gas is typically dictated by Cl2. Since their chemical compositions are different, they have different properties as well, although both are effective oxidizing agents.

Final Words

Chlorine dioxide gas, widely used for disinfection and sterilization in industrial applications, can pose significant threats to people working with it, necessitating continuous gas detection. Due to its high reactivity, chlorine dioxide must be kept away from compounds it could react with, as interactions may lead to fire or explosion. Chlorine dioxide gas detectors, available in fixed or portable configurations, accurately measure the gas concentration and alert users when levels become dangerously high. These detectors are crucial for reducing the risk of chlorine dioxide-related accidents. Gas detection retailers offer chlorine dioxide detectors for purchase online, along with calibration services to ensure accurate and reliable monitoring of this hazardous gas.

    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