The Evolution of Gas Sensing Over the Years: A Brief History
Believe it or not, the earliest gas leak detector was a singing canary. Yes, these tiny birds would be set up in cages inside coal mines. Because of their unique respiratory systems, they could detect airborne toxins, and the moment the canaries started shaking and stopped chirping, it worked as an alarm for the miners to evacuate immediately. Thankfully, the world of gas sensing has come a long way from that.
In this article, we take you through the evolution of sensors from bulky, expensive instruments to ultra-sophisticated, reliable, multi-tasking units that are as small as the size of an m&m.
What Does the Gas Sensing Market Look Like - Some Trends
The global gas sensor market is pegged to grow from 3.16 Billion in 2022 to 6.2 Billion by 2030, with a CAGR of 8.81% in the forecast period. This growth is driven by a demand for miniaturized wireless IoT-integrated gas sensors across industries, including defense, oil & gas, healthcare, and manufacturing of HVAC systems and air quality monitors, to name a few. Among sensing technologies, the market for electrochemical sensors is booming as these are known to be intrinsically safe, low cost, and work with high sensitivity and accuracy.
End user-wise, the industrial segment is a key driver, with oil & gas, chemical, and power generation increasingly relying on sensors to detect toxic and flammable gases as well as keep emissions of greenhouse gases in check. In terms of opportunities, the adoption of oxygen sensors in the medical sector has become popular after the COVID-19 pandemic to catch oxygen leaks and manage sufficient supply for patients on ventilators.
Regionally, Asia Pacific has dominated the sensor market due to growing urbanization and industrialization, and the need to monitor air quality. Meanwhile, stricter norms on vehicle emissions have boosted the adoption of gas sensors in Europe’s automotive sector.
Let’s Trace the Journey of Gas Sensors
There’s no denying the future of the gas sensor market looks promising, with companies set on making the average gas sensor more compact, intelligent, scalable, and low-cost. But how did we get here from the era of canaries? Let’s find out:
1. The Early 1900s: Combustible Sensors - Bulky and Small-Scale Application
It all started with a rather large catalytic combustion sensor created by Dr. Oliver Johnson in 1926. An employee of the Standard Oil Company in California, Dr. Johnson wanted to make operations safer by preventing blasts in fuel storage tanks. The sensor he developed could detect combustible mixtures in the air by burning gas inside to give readings of gases in the atmosphere. The catch? Besides being too big, this sensor required the user to keep pressing a button to get a fresh reading. Making it neither scalable nor portable.
2. The mid-1900s: Solid-State Electrochemical Sensors - Smaller, Portable, More Reliable
The mid-1900s saw a slew of innovations with the development of solid-state sensors. In 1952, American physicists John Bardeen and Walter Brattain discovered that semiconductor material like germanium modifies resistance depending on the atmosphere. What followed was one discovery after another, such as Tetsuro Seiyama demonstrating in 1962 gas sensing with simple electrical devices using thin films of zinc oxide. This detector was based on the absorption and desorption of gases influencing the electrical conductivity of semiconductors.
Things started picking up steam in Japan in the late ‘60s when driven by the need to control the increasing number of fire incidents in the country, Naoyoshi Taguchi made a metal oxide semiconductor or the first electrochemical sensor using tin oxide. He soon founded Figaro Engineering Inc, which has been ever since leading the way when it comes to commercial gas sensors. The sensors were now getting smaller in size, portable, and safer, with wider applications.
3. The 1980s-2010: Era of Miniaturization and Advancements
As sensors started getting more popular, there were growing concerns that had to be addressed, such as heavy exposure to oxygen dramatically reducing the age of a metal oxide sensor. Improving selectivity, tackling the interference of background gases, and enduring high humidity and temperature conditions were other factors that drove this era of advancements. Not to mention the shoebox-sized sensors of the mid-1900s still had a huge scope to be trimmed down.
The adoption of solid-state electrochemical sensors was spurred by the automotive sector’s need for oxygen sensing to control the air-fuel ratio and reduce smoke and pollution. Oxygen sensors were launched by the Robert Bosch Company in the 1970s in the form of unheated thimbles. The trouble was they didn’t work till reaching a temperature of 600 degrees Fahrenheit and couldn’t detect emissions during the critical engine start-up and warm-up stage. The unheated thimbles were swapped by heated thimbles to kickstart sensing during warm-up.
Every car manufactured since 1980 was required to have a functioning oxygen sensor to run the engine efficiently and reduce emissions. By the end of this era, there were multiple types of sensors in use across industries. These modern-day sensors were compact, highly sensitive, and IoT-integrated, offering real-time monitoring to protect the workers and enhance the safety and performance of the plant.
4. Today: Smaller than an M&M, AI-Enabled, Multi-Gas Sensing
In order to keep up with the growing applications across industries, today’s gas sensors should deliver high sensitivity, low costs, accuracy, compact size, responsiveness, and low maintenance. Nanostructured materials, with their high surface-to-volume ratio, offer plenty of advantages in gas sensing. These materials are being paired along with micro platforms such as micro-electro-mechanical-systems (MEMS) technologies to create high-performance sensors with remarkably high sensitivity and capability to detect vast numbers of gases.
Needless to say, these next-gen nanosensors require intelligent and real-time calibration of data. Enter artificial intelligence and machine learning. With such technologies built into the hardware, the time spent on manual calibration will be saved, making the sensor smarter and fit for large-scale deployment, more so than ever before.
Final Thoughts
With the gas sensing market poised to grow by leaps and bounds, we still see several companies that rely on outdated technology and methods of detection. While they’re still stuck in the earlier eras, at 21 senses, we are already at the forefront of the gas-sensing revolution.
Our sleek, compact hydrogen sensors are based on the highly sought-after solid-state electrochemical technology. Meanwhile, our multi-gas sensors tap into our patented nanochip technology, using smart algorithms to detect target gas at any concentration with unmatched accuracy. Click here to reach out to us.