Thermo Scientific Partisol & DataRAM

It measures them, but not in real time. The Partisol is a gravimetric sampler designated as a US EPA reference method for PM2.5 and PM10. It draws ambient air at a controlled flow through a size-selective inlet and collects the particulate on a filter. The mass concentration is determined afterward in the laboratory by weighing the exposed filter and dividing by the sampled volume. Because the result is a lab measurement, the PM2.5/PM10 values are not streamed live. Over the data link the sampler reports only its operating telemetry (ambient temperature, barometric pressure, sample flow and, if fitted, wind).

The 2025i is a sequential sampler: a 16-cassette magazine changes filters automatically for about two weeks of unattended daily sampling. The 2000i takes a single sample per run and needs a manual filter change. The '-D' dichotomous versions add a virtual impactor that splits PM10 into fine (PM2.5) and coarse fractions collected on two filters simultaneously. All four share the iSeries platform, the C-Link protocol, and the same reported telemetry, so the integration reads them identically.

It speaks the C-Link ASCII protocol over a serial line at 9600 baud, 8-N-1 (the iSeries also offers USB and Ethernet for local download). Each interval the integration polls the sampler for ambient temperature, barometric pressure, sample flow, and wind speed/direction, plus the instrument status and alarm flags. The sample flow is reported three ways: actual (volumetric at ambient conditions), mass, and standard-conditions flow.

Wind is not measured by the sampler itself. Wind speed and direction come from an optional external anemometer and vane wired into the sampler's two 0–5 Vdc analog inputs, so those values appear only when a meteorological sensor is fitted. Ambient temperature and barometric pressure, by contrast, are measured by the instrument's own sensors and are used for volumetric flow control.

The US-EPA reference flow for PM2.5 and PM10 sampling is 16.67 L/min, held by the instrument's mass-flow controller; the controllable range is roughly 10–19 L/min for other inlet configurations. Pump vacuum and filter pressure-drop are also monitored internally for flow control and filter-loading diagnostics, but they are instrument-health readings rather than environmental measurements and are not surfaced as parameters.

Both use the same Thermo light-scattering (nephelometric) engine and the same 0.001–400 mg/m³ auto-ranging measurement. The pDR-1500 is an active, pumped personal monitor (1–3.5 L/min) worn on the belt, with an integrated filter for post-gravimetric validation. The ADR-1500 is a fixed area monitor that adds an internal inlet heater to dry the sampled aerosol and remove the positive humidity bias at high RH.

Real-time particulate mass concentration (0.001–400 mg/m³, auto-ranging) plus air temperature, relative humidity, and barometric pressure, read over USB/RS-232 at 19,200 baud. Relative humidity and barometric pressure are also used by the instrument itself for volumetric-flow control and humidity-bias correction.

Size selection is by interchangeable cyclone at the inlet. The pDR-1500 ships with cyclones for PM10 & PM4 or PM2.5 & PM1; the ADR-1500 uses the GK 2.05 cyclone (roughly PM4–PM10) and the SCC 1.062 cyclone (roughly PM1–PM4). Removing the cyclone samples total/inhalable aerosol. The reported quantity is total mass concentration; the fitted cyclone defines the size fraction.