Dust Samplers

The HiVol 3000 dust sampler is designed primarily as a particulate sampler. The HiVol pump and flow controller draws a constant flow rate of ambient air through a specially prepared filter.

The air-borne suspended particles are collected on the pre-weighed filter over a pre-determined period. After sampling the filter is removed and re-weighed to determine the concentration of particulate matter (TSP, PM₁₀ or PM_2.5).

The total volume of air can be calculated from the flow-rate multiplied by the sampling time. Results are expressed as micrograms per cubic metre of air sampled (µg/m³), calculated at standard (or reference) conditions of temperature and pressure (STP). The display on the control panel of the HiVol 3000 dust sampler indicates the volumetric flow rate of air, and computes the sample volume corrected to STP conditions which means that no additional calculations are required during normal operation. This gives the HiVol 3000 dust sampler an advantage over other hi-vol types that control mass flow rate.

Volumetric flow control ensures that the air velocity through the Size Selective Inlet remains constant and ensures that the particle size cut point, which is based on velocity, does not vary. Other brands of samplers that only control based on mass flow will introduce an error when ambient pressure and temperature changes. This change in pressure and temperature effects the velocity at which particulates enter the size selective inlet, changes in velocity change the size at which particles are seperated by the inlet. Automatic correction to reference conditions eliminates average seasonal temperature and pressure corrections. This eliminates two sources of error that could otherwise introduce significant inaccuracies, and additional calculations.

The STP Reference conditions can be programmed into the HiVol. The Australian/European Standard Temperature and Pressure conditions are 0°C (273.15K) and 101.3 kPa.  In the United States, reference conditions are 25°C (298.15K) and 101.3 kPa. The HiVol must have the correct STP Reference conditions entered in the Setup menu, in order to report the “Corrected Sample Volume” to the appropriate reference conditions.