Considerations for Installing Gas Sensors

Natural gas is a hazardous gas with serious health implications. From sudden explosion to suffocation from inhalation, the effects of a natural gas leak can have both destructive and potentially lethal consequences. Because natural gas is naturally odorless and colorless, having a detection system programmed with natural gas sensors is essential. If you’re wondering where these sensors and gas alarms should be installed, consider the following:

• Nearby Hazardous Gases or Materials
• Weight Properties of Natural Gas
• Surrounding Air Flow

Nearby Hazardous Gases or Materials

What kind of materials do you deal with in your manufacturing processes? While you may work with natural gas or other combustible gases, there are certain areas more susceptible than others. Take a look at your equipment to determine where a leak could be discovered. Which hazardous places are frequented very often? Areas such as gas boilers, compressors, pressurized storage tanks, cylinders, or pipelines may require constant monitoring.

Pro Tip: If the natural gas detector is being mounted to a certain piece of equipment, ensure that the equipment is not prone to any vibration that could damage the gas detectors’ sensor.

Weight Properties of Natural Gas

Like many hazardous gases, the composition of natural gas is naturally lighter than air. The methane in natural gas causes the gas to gradually separate from oxygen in the air. In a confined space, it will rise. With these chemical properties in mind, it’s important to place your gas detectors in areas above the level of windows or doors where the gas may collect. 

Surrounding Air Flow

Lastly, the way a natural gas sensor is designed and air flowing nearby are important considerations. Most gas detection systems use ambient detectors that sense the presence of gas through the process of diffusion. In situations where gases may collect in inaccessible areas, the use of a sample-draw monitor is recommended. In every case, the goal of any gas detection system is to ensure that concentration levels of certain gases remain below hazardous levels.

Pro Tip: Keep in mind that while combustible gas detection systems are important during normal working hours, they are critically important during periods of inactivity when no employees are present and even small leaks can create dangerous and explosive concentrations of gas. 

Protecting Against Gas Leaks

If you regularly work with natural gas, having a detection system is a number one priority for your safety. Without adequate detection, your facility could be at risk for dangerous gas leaks and explosions. Determine which locations need constant monitoring in your industry and install a complete detection system for ongoing protection.

Connect with our sales team for more information about our natural gas sensors and detection solutions to keep you and your workers safe from hazardous situations.

In 1937, the unauthorized use of non-odorized gas at a New London Texas school caused a tragic explosion and fire that killed 294 people, both students, and teachers. Following the accident, federal authorities came together and determined that injecting odorous chemicals would help prevent a similar event from happening in the future. These regulations currently require gas companies to inject sufficient odorant such that a person with a normal sense of smell can readily detect a natural gas leak.

Natural Gas Odorants

Before understanding the process behind gas odorization, it’s important to review the common types of natural gas odorants. Since natural gas is completely undetectable by the human nose, chemical compounds are added to gas streams to create an odor. The most common odor associated with natural gas is “rotten eggs”, which is often attributed to the chemical mercaptan.

In its organic state, mercaptan has chemical properties similar to natural gas, making it a versatile odorant. However, depending on the application and particular environment, gas companies may use odorant blends of various organic sulfur and non-sulfur compounds. These may include tertiary butyl mercaptan, tetrahydrothiophene, isopropyl mercaptan, dimethyl sulfide, and methyl ethyl sulfide.

Gas Odorization Technology

Natural gas distribution companies consider ambient temperatures, soil conditions, and pipeline age when selecting the best odorant blends for their area. Because they are extremely concentrated, and because even the slightest leaks can lead to a large number of gas leak reports, liquid odorants must be handled properly. Many odorant manufactures will deliver the chemicals by truck or transportable containers designed to eliminate any leakage. 

Within the natural gas industry, there are three odorant injection technologies:

• Wick Style – Odorant is allowed to saturate a specially-designed wick suspended in a gas stream; odorant evaporates into the stream at a fixed rate.  Wick-type odorizers are generally used in smaller applications where gas flow is relatively constant. 
• Drip System – Odorant is gravity-fed through a needle valve and drips into the gas distribution pipe. The rate of flow is usually computer-controlled and varies by the amount of gas flowing in the pipe. 
• Injection System – Odorant is injected into the gas pipe using an electrical pump or pneumatic pump. The injection rate is also computer-controlled and varies as the gas flow increases or decreases. 

Pro Tip: Learn the correct terms! An odorant is the type of chemical being injected into the gas stream, and an odorizer is the type of equipment used for the process.

Monitoring Odorant Levels

To adhere to federal regulations, gas companies must maintain detectable gas odorization levels at one-fifth of the lower explosive limit. Proper monitoring of odorant levels is critical, as too little odorant provides insufficient protection, and too much can result in widespread gas leak calls by industrial and residential consumers. GDS Corp offers two families of odorant monitors to protect your gas pipelines:

• GDS-68SXP Advanced Natural Gas Odorant Monitor – Advanced remote odorant monitor designed for unattended, low-power operation. Supports automatic calibration, remote satellite monitoring and more.
• GDS-68XP Natural Gas Odorant Process Monitor– Process monitor designed to measure H2S. mercaptans and other gases in process flow applications. Uses low-cost electrochemical sensors and minimizes the amount of gas released into the environment. 

Protect Your Employees and Equipment 

Gas odorants play a critical role in protecting customers’ lives by ensuring that natural gas leaks are detected and repaired before hazardous conditions exist. Whether it’s injecting gas odorants, or monitoring gas odorant leaks around gas odorizing equipment, it’s crucial for your facility to have a reliable gas detection system.

Connect with our sales team to find a detection system customized for your specific environment.

Gas distribution companies must adhere to strict regulations to ensure the safe use of natural gas since it is highly combustible and odorless. Mercaptan compounds, tetrahydrothiophene (THT), and dimethyl sulfide (DMS) are among the most popular chemicals added to natural gas. Both the sulphuric elements and versatility of mercaptan make it a highly effective odorant. Learn more about this fuel additive to help you guard against potential gas leaks.

That Rotten Egg Smell

If you regularly work with natural gas, you’re probably accustomed to the “rotten egg” smell of gas odorants. While the specific odor may vary slightly based on the type of odorant, most gas companies strive to create a universal smell. Mercaptan compounds, specifically, contain the sulfur and hydrogen compound, hydrogen sulfide (H2S) to create a distinctive aroma unlike any other. 

Versatility of Mercaptan

Mercaptan is a non-toxic substance that is made of carbon, hydrogen, and sulfur. Because it’s regularly found in nature as a waste product for both animals and humans, mercaptans are also organic and extremely foul-smelling. That being said, mercaptans provide a number of advantages for industrial purposes.

• Low Requirements – Small amounts, specifically less than one part per million, of mercaptan, are necessary for human detection.

• High Performance – As a non-corrosive and nontoxic sulfuric compound, mercaptan can be applied in a number of ways.
• Similar Properties – In a gaseous state, mercaptan has chemical properties similar to natural gas and will evaporate in the same manner.

Other Types of Additives

Depending on your specific application, chemical compounds may be used singularly (like tetrahydrothiophene) or as a mixture with other compounds to create a gas odorant. The types of additives available may vary based on your location and specific industry, but will likely include these compounds:

• Dimethyl Sulfide
• Isopropyl Mercaptan
• Methyl Ethyl Sulfide
• Normal Propyl Mercaptan
• Secondary Butyl Mercaptan
• Tertiary Butyl Mercaptan
• Tetrahydrothiophene

It’s important to inject the appropriate amount of gas odorant to give natural gas a detectable smell. A small concentration of mercaptan compounds could put your safety at risk and excessive levels may result in costly service calls for suspected leaks.

Pro Tip: Not all gas odorants smell the same, making it essential for manufacturers to install a complete gas detection system to monitor concentration levels.

Safe Gas Odorant Monitoring

If you are a gas company that regularly distributes natural gas streams to homes or businesses, it’s crucial to have a reliable monitoring system. GDS Corp offers a number of natural gas odorant monitors to help you maintain optimal levels of mercaptan and THT odorants in your gas streams.

Connect with our sales team to find a gas distribution solution to meet your specific needs and applications.

What Are The Dangers of Natural Gas?

Since natural gas is naturally invisible and odorless, it can be hard to detect at high concentrations in the air. To combat this problem, natural gas distribution companies are required to add a form of mercaptan, a chemical that smells like rotten eggs. At low concentrations, escaping natural gas can be detected by smell; however, relying entirely on your sense of smell can be disastrous. 

Furthermore, in some cases, natural gas used in some plants may not contain any odorant and so would go undetected. Without a natural gas detection system in your manufacturing processes, the health your workers could be at risk in the following three ways.

1. Decreased level of oxygen
2. Release of carbon monoxide
3. Risk of a flash fire or explosion

1) Decreased level of oxygen

Leaking natural gas can replace oxygen in ambient air. Without oxygen, you will be unable to breathe, resulting in a range of symptoms including:

• Headache
• Dizziness
• Nausea
• Eye and throat irritation
• Fatigue
• Breathing problems
• Pale skin or blisters from skin contact

2) Release of carbon monoxide

One of the primary uses of natural gas in industrial applications is to provide heat. This requires that the gas be burned in the presence of air. If natural gas is burned without sufficient oxygen, the incomplete combustion process creates carbon monoxide, a highly toxic gas that is very dangerous to humans. 

Carbon monoxide usually extrudes an extremely pungent odor and can cause a round of dangerous health effects. That being said, carbon monoxide poisoning looks very similar to natural gas poisoning, with severe cases having deadly consequences.

Pro Tip: Each of our detectors can be customized for equipment or facility. Install a carbon monoxide sensor as part of your gas detection system to monitor unsafe gas concentration levels in your vicinity.

3) Risk of a flash fire or major explosion

Finally and most importantly, leaking natural gas can quickly become an explosive hazard. It only takes a concentration of five percent (5%) by volume to create an explosive atmosphere. And there will be a source of ignition! 

Any combustible gas detector system should include highly visible warning strobes and loud horns to indicate the presence of a leak and give employees a chance to leave the premises before hazardous conditions exist. In addition, the gas detection system can be programmed to trigger exhaust fans and close gas valves in the event of a warning indication. 

How to Respond to a Suspected Gas Leak

To guard against the health risks of a potential natural gas leak, it’s important to know what to do if you. In the case of an emergency, immediately call 911 to contact the fire department for further assistance. If the leak is suspected outside and you’re not in immediate danger, follow these instructions:

• Mild Gas Leaks – Leave the area if you’re not sure of the leak’s extent.
• Severe Gas Leaks – Leave the surrounding area as soon as possible. Due to the flammability of natural gas, a simple phone call uses enough energy that could ignite a fire. Drive away from the area and contact emergency personnel for further assistance.

Caution: Whatever you do, don’t underestimate the power of natural gas. If there is a suspected gas leak, any source of electricity can create an explosion. Do not touch any electrical components in your vicinity until the natural gas levels are under control.

Prepare for Natural Gas Leaks

Burning natural gas is a safe and common practice, but without proper safety detection, it can cause a myriad of health issues. Install a safety detection system to help prepare for a natural gas leak before it’s too late. 

Don’t put your health at risk. Connect with our gas detection experts to find the right monitor system for your industrial applications.