engineering recuitment NHPC JE & THDC JE 2023 Mock Test Environmental Engineering Air and Noise Pollution
According to different agencies including central pollution control Board (CPCB) the NCR region had crossed the pollution danger level with extremely high concentration of PM 2.5 content in the air. PM 2.5 refers to
1
Particular matter having diameter < 2.5 mm
2
Particular matter having diameter < 2.5 μm
3
Particulate matter having diameter < 2.5 μm
4
Particulate matter having diameter > 2.5 mm