Which combination of sensors is commonly found on the MultiRAE Pro?

• A. CO2 and H2S
• B. Methane and Hydrogen
• C. Oxygen (O2) and CO2
• D. Oxygen (O2) and LEL

Answer: (D)

A portable multi-gas monitor like the MultiRAE Pro is commonly configured to protect workers by tracking two fundamental hazards in many environments: oxygen levels and flammable gases. An oxygen sensor tells you if the atmosphere is safe to breathe—whether it’s deficient or enriched—while an LEL sensor detects a wide range of combustible gases and gives a quick read on flammability risk. Together, these two sensors cover the most critical safety concerns that appear first in many industrial settings, providing a broad early warning with a single device.

Other sensor pairings tend to focus on specific gases or environmental measurements that aren’t as universally required for initial safety monitoring, which is why the combination of oxygen and LEL is the standard baseline.