The air volume hood is an instrument used to measure the air volume from the low-pressure ventilation duct to the atmospheric vent. The wind is collected by the wind collecting hood to the wind speed uniformizer on the base, and the air volume value is calculated by measuring the wind speed change value on the uniformizer and the ventilation cross-sectional area of the base, and the air volume is directly displayed by the measuring instrument.

The working principle of the air volume hood is to use the wind pressure sensor or thermal sensor on the end face of the base to measure the wind speed and take the average value, and multiply it by the ventilation area of the base to get the air volume value.

Professional terms

Air volume:the amount of air circulating per unit time. The unit is m/hr.

Digital air volume hood:A wind collecting hood is used to collect wind to the wind speed uniformizer on the base. The air volume value is calculated by measuring the wind speed change value on the uniformizer and the ventilation cross-sectional area of the base, and the air volume is directly displayed through the measuring instrument.

The air volume hood is generally composed of a host with digital display, a hood kit, a handle and a base (as shown in Figure 1)

Technical parameter requirements

The specification of the hood kit in the standard accessories is 610*610mm. Please confirm the size of the air outlet to be sampled before purchasing. The hood kit must completely cover the air outlet to ensure the accuracy of the data.

Air volume range:42-4250m³/hr

Accuracy:±3% of reading or ±12m³/hr (air volume >85m³/hr)

Resolution:1m³/hr

The multi-functional air volume hood host can be disassembled and used separately to measure air volume, pressure and relative humidity

Wind speed range:(Pitot tube) 0.125-78m/s

(Airflow probe) 0.125-25m/s

(Matrix probe) 0.125-12.5m/s

Accuracy:±3% of reading or 0.04m/s

Resolution:0.01m/s

Pressure:(differential pressure) ±3735pa (maximum 37.5kpa)

(absolute pressure) 356-1016mmhg

Accuracy:±2% of reading

Relative humidity (temperature and humidity probe)

Range:5-95%HR

Accuracy:±3%HR

Resolution:0.1%HR