While catalytic bead sensors have been in use for many years, infrared sensors are gaining popularity due to their increased reliability and longer life. Understanding the differences between these two major technologies is important as you determine how to configure your gas detection system. In the case of methane gas, it’s crucial to have a sensor you can rely on in your specific environment.

What is Methane Gas?

Did you know that natural gas is made up of nearly 87% methane? Like other combustible materials, methane gas is highly flammable and presents a huge risk for those dealing with natural gas. In its organic state, it is odorless, colorless, tasteless, and nontoxic. As a major greenhouse gas, it is produced during the anaerobic decomposition of manure or in the production of chemicals such as acetylene and methanol.

As a component of natural gas, it is known to rise and accumulate in certain areas of enclosed buildings. If a sufficient amount is present, it will replace the oxygen and may create a long term asphyxiation hazard if allowed to accumulate. If the percentage increases beyond five percent by volume, it becomes a very dangerous explosive mixture. 

Unsafe Levels of Methane

Methane gas that has not been odorized can be very difficult to detect without proper combustible gas detection equipment. According to biotechnology scientists, methane gas has not been shown to be toxic but can cause an explosion (the Lower Explosive Limit)  when one volume of methane is mixed with 20 volumes of air (~5% by volume). With that in mind, a gas detection system can be configured to measure the LEL value in real time. Typically, gas detection systems are programmed to generate a warning if the measured value reaches 20% LEL and an alarm if the measured value reaches 40% LEL. 

Catalytic Bead vs. Infrared Sensor

If you regularly work with methane, a byproduct or component, it’s important to understand the two types of sensor technologies used to detect methane gas.

• Catalytic Bead Sensors – Preceding the use of infrared sensors, catalytic bead sensors usually cost less and have the ability to detect other combustible solvent vapors in the environment. Working as a Wheatstone bridge circuit, the active filament wound in a catalytic bead sensor uses a platinum wire with a palladium-based catalyst. Unsafe levels of methane are detected when the resistance ratio between the active and reference bead changes.

• Infrared Sensors – Due to the risk of catalytic bead poisoning in environments involving silicone, lead, sulfur, or halogenated compounds, infrared sensors were introduced as an alternative. Using two wavelengths of infrared energy, infrared technology compares the  outputs of the gas absorption beam and reference beam to determine if gas is present. Because infrared sensors don’t require oxygen to operate, they can be reliably used around a number of applications without issue. Furthermore, typical infrared sensors include a microprocessor that continuously checks the sensor for proper operation. 

Pro Tip: Methane gas is often combined with an odorant that smells like rotten eggs to help you detect leaks. If you smell a peculiar odor, be sure to survey your equipment or call for assistance.

Real-Time Detection

Both catalytic bead and infrared sensors can be configured to detect methane gas, and both have certain advantages. GDS Corp offers gas detectors that utilize both technologies to give you accurate information no matter what environment you’re in.

Connect with our sales team to customize a methane detection system for your particular

Portable Methane Monitoring

Due to most industrial facilities having numerous confined spaces where workers spend time analyzing, installing, and repairing various types of equipment, methane monitoring is crucial for these areas. Since a gas buildup can occur in a matter of minutes in these areas, workers will have very little time to react in an emergency. However, to avoid these situations, companies now equip maintenance technicians and others working in these areas with portable methane gas detectors. Small and versatile, these detectors can be either handheld models, or perhaps ones made to be clipped to shirts or belts. In either case, workers using portable methane detectors can complete their tasks safely, while also having access to real-time data regarding gas levels.

Stand-Alone Sensing Technology

While for many years industrial plants, offshore drilling platforms, and other facilities relied on having multiple CH4 gas sensors installed throughout an area to monitor methane, today’s technology is moving more toward relying on stand-alone sensors. With this technology, only one sensor is needed to monitor a large area, and they can be programmed to monitor for other dangerous gases as well. Though the price tag on these methane gas sensors can run well over $10,000 or more, many companies feel they are making a smart investment in keeping their workers and facilities safe from disaster. Considered to be accurate, reliable, and long-lasting in various types of work environments, stand-alone sensors utilize state-of-the-art electronics to closely monitor gas levels.

Audible and Visual Alarms

Since a methane gas leak can occur in many different types of areas within an industrial facility, modern methane detection systems rely on multi-faceted alarm systems to alert workers to dangerous conditions. Therefore, systems are equipped with audible and visual alarms, which can be adapted to all work environments. For example, in areas where workers may be spread out over long distances, such as a pipeline, sirens can be very effective in signalling danger. However, in facilities where noise levels may be high and sirens would not be easily heard, visual alarms such as flashing lights can be used to keep workers safe.

Wireless Technology

Since modern detection systems use wireless technology to link to data networks, they not only send out real-time data 24/7, but also require little calibration. In addition to this, sensors can also be monitored by on-site personnel, as well as engineers in monitoring centers miles from the facility.

Portable Detectors

Since many workers find themselves spending much of their time in confined spaces, the need for portable detectors has expanded tremendously in recent years. Because there are a number of different types of portable LEL gas detectors, pricing can vary. Some can cost less than $200, and come with flexible goosenecks that can be put in hard-to-reach areas. Able to be clipped onto belts or shirts, they can monitor for methane, acetone, ammonia, hydrogen sulfide, lacquer, and many other gases and solvents.

Confined Space Kits

Along with a single portable detector, many companies now purchase kits specifically customized for confined spaces. Able to detect methane, oxygen, carbon monoxide, and hydrogen sulfide, they are equipped with multi-alarm systems such as visual, vibrating, and audible, guaranteeing they can provide a safe environment in numerous ways. Sampling gases from as far away as 66 feet, these detectors are also made to operate in extreme temperatures, often ranging from below zero to over 120 degrees Fahrenheit. Equipped with rechargeable batteries, the LEL sensors have a battery life of 12 hours, enabling them to be used in a variety of work environments for long periods of time. While in some cases costing $3,000 or more, they are considered well worth the investment.

Fixed Multi-Gas Detectors

When it comes to fixed multi-gas detectors, pricing can vary widely depending upon their features. With many of these detectors being self-calibrating, very little maintenance is required. In addition to this, they are equipped with the latest in wireless technology, making them capable of transmitting real-time data to locations miles away. Able to be used in such work environments as pipelines, refineries, offshore platforms, semiconductor manufacturers, and chemical processing plants, they have multiple alarm systems that can alert workers who are nearby as well as those who may be located much further away. Prices for fixed detectors can vary, ranging from just over $1,000 to more than $10,000.

Seek Out Knowledge and Experience

Because there are so many different types of methane gas detectors, it’s important to know what you need prior to making a purchase. To ensure you get the best equipment for your company, contact GDS Corporation today and get your questions answered by knowledgeable and experienced industry professionals.

Undetected Vapors

When workers are busy installing new equipment or conducting repairs, they are using numerous tools as well as putting themselves in situations where gas vapors can begin to accumulate. If this happens, disaster can result in a matter of moments. To ensure this does not happen, methane gas detectors are equipped to be extremely efficient in detecting even the smallest levels of methane, enabling workers to quickly evacuate the area.

How Does Methane Accumulate in Confined Spaces?

Because it’s colorless, tasteless, and odorless, methane can be a very difficult gas to detect before it’s too late. Along with this, it’s also able to travel long distances underground, allowing it to easily find its way into numerous types of confined spaces. With such common points of entry as floor and wall cracks, floor drains, sewer pipes, and utilities, it can accumulate in such confined spaces as crawl spaces, wall cavities, and other areas. Whether it’s a confined space on an offshore platform or within a chemical processing plant, the possibility of methane accumulation remains quite high.

Lower and Upper Explosive Limits

Even though methane is relatively non-toxic, the greatest threat comes in its ability to catch fire and explode rather quickly. In most cases, methane in confined spaces explodes at concentrations between 5%-15%, with most explosions occurring at levels of 9% or higher. Due to the high risks associated with methane, many companies now invest in methane Ch4 gas detectors to help protect workers.

Installing Methane Gas Detector Alarms

Since methane gas is lighter than air, the highest concentrations of it within confined spaces are usually found near ceilings. Because of this, a methane gas monitor in a confined space should always be installed no more than six inches from the ceiling, and should also be installed close enough to corners so that methane accumulations won’t be allowed to build up in these areas.

High Levels of Safety

By installing methane detectors in confined spaces as well as giving employees portable monitors to clip onto their belts or shirts, safety levels can increase dramatically. Since data from these monitors can be transmitted in real-time to management personnel as well as emergency workers located in nearby monitoring centers, most potentially dangerous situations can be handled quickly and with much more efficiency.

By contacting GDS Corporation today regarding methane accumulation in confined spaces, your company can find itself having greater peace of mind, knowing employees, equipment, and facilities are well-protected against potentially catastrophic situations.

Remote Locations

Because many natural gas pipelines are located in remote settings, it’s crucial they have alarm systems that can alert workers of dangerous situations as soon as possible. On most pipelines, methane detectors have a combination of visual and audible alarms, allowing workers located both near and far to be quickly alerted to potential trouble. For example, workers who may be located long distances from the problem will be alerted by the sirens, while those located nearby will hear the siren and see flashing lights and strobes.

Weather Conditions

Along with their remote locations, natural gas pipelines can also be located in areas that are prone to harsh weather conditions. Hot or cold temperatures, fluctuations in humidity levels, sand or dirt, and more can all add up to potentially cause problems with the sensors. To keep these problems from developing, today’s methane gas detector is now able to withstand virtually any type of weather, due to being a self-contained unit. By having this technology, the sensors need very little calibration in order to provide accurate readings at all times.

Central Location Monitoring

In years past, numerous sensors had to be installed on natural gas pipelines to ensure constant monitoring of the entire pipeline. However, rather than installing a methane gas sensor every few feet, companies today are often able to install only one monitor in a central location to provide readings for the entire pipeline. In addition to the obvious advantage of only needing one sensor, companies can also use these monitors to scan for a variety of gases in addition to methane. Yet while these sensors are considered state-of-the-art for their accuracy and reliability, they do come with a large price tag, often costing up to $25,000 or more. However, based on the investment companies make in equipment and training of employees, the sensors are seen as a smart investment that will pay dividends over time.

Data Transmission

If an emergency develops, emergency personnel must have access to real-time data to make the proper decisions regarding evacuations, equipment shutdowns, and other factors that may come into play. Due to the seriousness of these situations, methane detection systems are equipped with wireless technology that transmits real-time data to monitoring technicians.

To ensure your natural gas pipeline stays as safe as possible, contact GDS and speak with a knowledgeable applications engineer who can answer all of your questions.

Standalone Individual Sensors

If you have a large facility to monitor and want many sensors located at key points where methane could pose a danger, it may be best to install standalone individual sensors across your facility. Especially good in areas where large numbers of people congregate or work, these sensors are easy to install and can relay data to personnel in other locations to alert them in the event methane is detected. While these sensors offer the advantage of being located throughout the facility, they will need to be calibrated on a regular basis, which will require having an adequate number of personnel trained in the calibration process.

Multiple-Location Monitors

For those locations where a methane gas sensor that could monitor multiple locations would be more convenient, it may be best to purchase a multiple-location monitor. More expensive than individual standalone monitors, they can monitor up to 32 separate locations within a facility, making them much more convenient. In addition, they can also relay data from multiple locations quickly and accurately, making them a favorite of many companies. With data that can be accessed over the internet or through mobile devices such as smartphones or tablets, they offer high levels of safety and convenience.

Infrared Sensors

Considered the most up-to-date technology when it comes to methane sensors, an infrared sensor is well-known for being a high-sensitivity methane sensor. Requiring no oxygen to operate, infrared sensors can be used in a wide variety of places including offshore rigs, processing plants, and pipelines. Since they require no oxygen, they can be easily adapted to numerous work environments, and can operate very reliably under extreme environmental conditions such as heat, cold, humidity, or dust.

Catalytic Bead Sensors

While many companies have replaced these sensors with infrared sensors, catalytic bead sensors have a long track record of being very accurate and reliable. Popular with companies because they are inexpensive, they do need to be calibrated often and can also be prone to contamination from lead or sulfur. Because of this, they do need to be replaced more often than infrared sensors, which can increase their overall cost. However, because of their reliability in providing very accurate results, many companies that have used these for decades tend to be very reluctant to change course with their sensors.

1: Create An Evacuation Chart

You must place maps in your facility that show a clear evacuation route for each employee. Draw arrows that explain how people may exit the building, and mark areas outside the building that are at a safe distance. The evacuation chart may prevent trampling and chaos when you are trying to get everyone out of the building.

2: Shut Down Everything

You must have emergency shutoff buttons on all your machinery. Your employees must be trained to shut down operations when the alarm goes off, and you may shut down the plant from your office. The emergency lights must stay on for evacuation purposes, but everything else in the building must stop running. A single spark could ignite the methane gas that set off the alarm.

3: Start The Blower Fans

Your facility must have blower fans that will suck the methane gas out. These fans must run on remote power sources that will not ignite the gas, and you must turn on the fans before you leave the building. You may use a remote system to turn on the fans, or the power switch for the fans may be located outside the building.

4: Do A Head Count

You must think of yourself like the principal of a school. Take a head count of every employee at work that day, and ensure you know where those employees are. Emergency response crews must know if there is someone in the building who must be rescued, and you may be held liable if an employee is left in the building under hazardous conditions.

5: Call For Assistance

You must have a hazmat team on speed dial for these occasions. The hazmat team can enter your building safely, check for the source of the methane leak and start the fans in your building if you could not. The hazmat crew can check the levels of methane in the building, and the crew will tell you when the building is clear. You must not attempt to enter your building for any reason until you have been told to do so by a hazmat professional.

The five steps above will help you respond appropriately to a methane gas leak. The methane sensor you installed will sound a loud alarm when levels are too high, and you must follow the steps here to keep everyone in the building safe. Do not skip any steps in this list, and ensure you have contacted emergency response crews who can clear the building for you.