In the field of gas detection and safety, ppm (parts per million) and LEL (Lower Explosive Limit) are two key but completely different concentration units used to describe the hazardous characteristics of hydrogen.
The fixed hydrogen gas detector is a detection device that can measure the concentration of hydrogen in the air environment and issue an audible and visual alarm in a timely manner when the concentration exceeds the set value. When selecting a hydrogen detector, there are different requirements for measuring ppm and %LEL. Different requirements also result in different configurations of gas detectors. What are the specific differences?
The %LEL test measures the flammability (i.e., flammability and explosiveness) of hydrogen. It is set on the basis the lower explosive limit of hydrogen. The lower explosive limit is divided into 100 parts, and the range of 0-100%LEL is the detection range of the hydrogen alarm for flammability. Measuring PPM is to measure the toxicity of hydrogen. It is set based on the safe proportion of hydrogen in the controller, and the detection unit is defined as PPM.
For measuring flammability (%LEL), gas detectors usually have built-in catalytic combustion sensors, while for measuring PPM and toxicity, dedicated electrochemical sensors are used. The prices of gas detectors with different sensor configurations also vary. Therefore, when selecting a model, it is essential to first understand the measurement requirements clearly and choose the appropriate hydrogen detector based on those needs.
Our company, Xi 'an Huafan Technology Co., LTD., has been dedicated to gas detection and alarm devices, flammable, explosive, toxic and harmful gas detection and alarm equipment, environmental monitoring and analysis instruments, and providing complete industrial safety and environmental monitoring system solutions for over 20 years. We specialise in industrial gas detectors integrating R&D, design, production, sales and service. The company is committed to becoming the most professional supplier of on-site testing instruments and system solutions at home and abroad.