What is used to check air quality in the material?

• A. Multimeter
• B. Gas Detector
• C. Hygrometer
• D. Anemometer

Answer: (A)

Gas detectors are the instrument used to check air quality in a space or material because they are designed to sense the presence and concentration of specific gases in the air, including hazardous or oxygen-deficient conditions. In wastewater operations, monitoring for gases like hydrogen sulfide, methane, ammonia, or low oxygen is essential for safety and process control, and a gas detector provides real-time alerts when levels become dangerous. A multimeter measures electrical properties and isn’t built to detect gases. A hygrometer gauges humidity, which is only one aspect of air quality, not the overall gas composition. An anemometer measures air flow speed, not gas concentration. So the gas detector best serves the purpose of assessing air quality.