Five-Gas Monitoring: Advanced Detection for Hazardous Industries

Five-Gas Monitoring: Advanced Detection for Hazardous Industries

Jackie Cappucci | Tuesday, October 1, 2019

Gas hazards. Almost every industry has them. Are you monitoring the ones that could grind your operations to a halt?

On any given day, your workers have the potential to encounter gas hazards that can endanger them and put your projects or business at risk. Unfortunately, you can’t see or smell many of these gas hazards – and if you can, it might be too late. That’s why you need gas detectors. Personal gas detectors continuously monitor the composition of air in your breathing zone to provide the awareness you need to protect yourself and make smart decisions.

Although there is no “silver bullet” gas monitor that will detect every possible combination of gas hazards, a multi-gas monitor is a good place to start. Using a properly-configured five-gas monitor, like the Ventis® Pro5, allows you to advance the level of detection, giving you better awareness of the gas hazards around you.

The hazardous gases you should monitor vary by industry, so the combination of sensors that you choose for one application may not provide the same detection coverage in another. For the most accurate detection, customize your sensors to monitor the gases you’re most likely to encounter in your application or those that could pose the most danger should they be present.

Review the information below to determine which gases to monitor for your industry.

Pulp and Paper, Water Treatment, Shipyard

The main gases of concern are methane (CH4), hydrogen sulfide (H2S), and a lack of oxygen. Hydrogen sulfide and methane are released when organic materials decompose, and their buildup can lead to a lack of oxygen and can explode when coupled with a source of ignition.

There may be additional gas hazards present that are too numerous to name. Beyond the big three gas hazards are the dangers that exist from purifying chemicals like ammonia (NH3), chlorine (Cl2), or chlorine dioxide (ClO2) that are used to decontaminate waste and effluent water. In addition, waste from the industrial base in the community could contain any number of toxic or explosive gases.

Chemical Refining

Chemical refining processes typically involve hazardous materials with very low flashpoints, low LELs (lower explosive limits) and a wide flammable/explosive range. LEL is the lowest concentration of a gas or vapor in air that will burn when exposed to an ignition source. For many flammable gases, the LEL is less than 5% by volume, so there is a high risk even when relatively small concentrations of the gas escape into the atmosphere.

Toxic gases used in chemical refining, like ammonia (NH3) and chlorine (Cl2), typically need to be detected in sub-100ppm (0.01%) volume levels to protect personnel and are therefore detected using different types of sensors. Ammonia, a colorless gas with a pungent odor, is a widely used chemical that is commonly found in a variety of industrial environments. When combined with some substances, like chlorine, it will react explosively.

Food and Beverage

Perhaps the most common gas in the food and beverage industry is carbon dioxide (CO2). Carbon dioxide is frequently used to provide carbonation to drinks, keep items cold in the form of dry ice, and is produced by leavening agents like yeast. Because carbon dioxide is heavier than air, it can cause suffocation when present in high concentrations, and thus is best monitored in combination with oxygen.

Food and beverage companies also use many tons of ammonia (NH3) for refrigeration, flash freezing, and bulk storage, all running the risk of gas releases.


In many cases, when emergency responders arrive at a hazardous materials scene, they are unaware of whether the area contains harmful or deadly chemicals. Five-gas monitors enable first responders to continuously monitor the scene for a variety of different gas hazards. Hazmat responders may encounter carbon dioxide (CO2) leaks, chlorine gas (Cl2), hydrogen sulfide (H2S), sulfur dioxide (SO2), as well as any number of potentially explosive substances, depending on the call.

If you work in an industry that could benefit from five-gas monitoring, don’t risk working without a gas detector. Browse our gas hazards and sensor configuration chart or talk to one of our experts to find the right sensor configuration for your application.