Combustible Gas Detection: PureAire’s Expert Guide to LEL Safety
- By : PureAire Monitoring Systems
- Posted on : June 16, 2025
- Combustible Gas Monitors, News Room
Basic Knowledge on Gases
Combustible gas detection is critical for preventing fires and explosions in industrial settings. When gases like hydrogen, methane, or propane accumulate and reach explosive limits, even a minor spark can trigger a catastrophic event. At PureAire Monitoring Systems, we specialize in real-time detection technologies that identify dangerous gas levels well before they pose a threat—ensuring continuous safety and compliance.
What Is a Combustible Gas?
A combustible gas is any gas that can ignite and burn when mixed with air and exposed to a source of ignition. Common examples include:
- Hydrogen (H₂)
- Methane (CH₄)
- Propane (C₃H₈)
- Isobutane (C₄H₁₀)
- Ethanol and Methanol
These gases are essential to industrial processes, but require strict monitoring to avoid combustion risks.
Understanding Explosion Limits (LEL & UEL)
Explosion limits refer to the range of gas concentrations in air that can ignite:
- LEL (Lower Explosive Limit): The lowest concentration at which a gas can combust.
- UEL (Upper Explosive Limit): The highest concentration at which a gas can still ignite.
Here are some common explosion limits:
Gas | LEL (%vol) | UEL (%vol) |
---|---|---|
Hydrogen | 4.0 | 75.6 |
Methane | 5.0 | 15.0 |
Propane | 2.1 | 9.5 |
Iso-butane | 1.8 | 8.4 |
Toluene | 1.2 | 7.0 |
Methanol | 5.5 | 44.0 |
Ethanol | 3.5 | 19.0 |
PureAire’s combustible gas detection diagram visualizing the explosive range between the Lower and Upper Explosion Limits (LEL and UEL), with alarm set below 25% LEL.
PureAire’s Combustible Gas Detection Technology
PureAire offers industry-leading gas detection systems engineered to keep environments safe from combustible gas hazards. We now proudly offer the new MPS™ Flammable Gas Monitor, a revolutionary sensor that detects up to 15 flammable gases with no calibration required.
Now Featuring: The MPS™ Flammable Gas Monitor
Unlike traditional catalytic bead or MOS sensors, the MPS (Molecular Property Spectrometer™) delivers accurate, real-time gas classification without cross-interference or drift. It requires no calibration over its lifetime, cutting downtime and maintenance costs.
- ✔️ Detects Hydrogen, Methane, Propane, Ethanol, Butane, Ammonia, Acetylene, and more
- ✔️ No false alarms from humidity, temperature, or interfering gases
- ✔️ Lifetime factory calibration – no recalibration needed
- ✔️ Certified to UL 2075 and ATEX/IECEx standards
- ✔️ Modbus or 4-20 mA output for PLC/SCADA integration
View Full Specs of the MPS Flammable Gas Monitor →
Sensor Options Tailored to Your Application
Depending on your environment and gas type, we also offer:
- Metal Oxide Semiconductor Sensors (MOS): Ideal for general hydrocarbon detection.
- Catalytic Bead Sensors: Time-tested for combustible gas monitoring.
- Electrochemical Sensors: Accurate for toxic flammable gases like ammonia.
Our solutions ensure compliance with LEL safety thresholds and integrate seamlessly with emergency systems, alarms, and facility controls.
Applications Across Industries
- Hydrogen Production: High-range explosion limits require fast-response detection.
- Chemical Labs: Real-time propane and methane monitoring during experiments.
- Industrial Plants: Combustible leak detection in confined spaces.
Why Choose the MPS Flammable Gas Monitor from PureAire?
- ✔️ Measures 14+ Gases and Gas Mixtures
- ✔️ Engineered to exceed EN50194 and UL1484 standards
- ✔️ Low-maintenance, long-life sensors (up to 15 years)
- ✔️ Full integration with SCADA, PLCs, and IoT monitoring platforms
For over 25 years, institutions and facilities across science, technology, manufacturing, and healthcare worldwide have trusted PureAire’s industry-leading gas detection systems in the most demanding applications.
Get Started with Safer Combustible Gas Detection
Contact our experts today for a consultation or request a custom quote on our MPS Flammable Gas Monitor.