Airmetrics MiniVol XP (and TAS) Portable Air Sampler Go to product viewer dialog for this item.
is a lightweight, low-flow device jointly developed by the US EPA and Airmetrics to sample ambient air for particulate matter (PM10, PM2.5, TSP) and non-reactive gases. It operates at a target flow rate of 5 Liters per Minute (LPM). 1. Pre-Calibration Leak Check
Before conducting a calibration, you must confirm that the unit contains no air leaks.
Insert a test filter: Place a 47mm filter into the filter holder assembly and attach it to the sampler (do not use this filter for actual sampling).
Turn on the sampler: Let it run for at least 2 minutes to warm up.
Perform the leak test: While the pump is running, press and hold the Reset button (this overrides the low-flow shut-off circuit). Block the main air inlet firmly with the palm of your hand.
Verify: The rotameter ball must drop completely to zero and stay there. If it lingers above zero, there is a leak in your sampling train. 2. How to Calibrate the MiniVol
Calibration must be performed using a transfer standard (such as the MiniFlo Field Calibration Kit) that has been verified against a NIST-traceable primary standard within the past year.
[MiniFlo Transfer Standard] ──> [Filter Holder Assembly] ──> [MiniVol Inlet] │ (Pressure Tubing) ▼ [Digital Manometer]
Setup the Apparatus: Affix the MiniFlo transfer standard onto the inlet tube of the filter holder assembly. Connect a digital manometer or Magnehelic gauge to the pressure tap on the MiniFlo standard.
Environmental Baseline: Record the local ambient temperature ( Tactcap T sub a c t end-sub in Kelvin) and barometric pressure ( Pactcap P sub a c t end-sub in mm Hg).
Warm-up: Turn on the sampler and allow it to run for at least 2 to 5 minutes so the device and transfer standard can reach equilibrium. Multi-Point Calibration:
Adjust the flow control knob on the MiniVol until the physical rotameter reads exactly 6.5 LPM. Record the pressure drop (
in inches of water) on the manometer alongside the rotameter reading.
Adjust the flow control downward and repeat this process for increments of 6.0, 5.5, 5.0, 4.5, and 4.0 LPM.
Calculate the Flow Curve: Use the MiniFlo’s manufacturer-provided calibration equation to calculate the actual flow rate ( Qactcap Q sub a c t end-sub ) for each point. Plot Qactcap Q sub a c t end-sub against the sampler’s indicated rotameter readings ( Qindcap Q sub i n d end-sub ) to construct your mathematical flow curve. 3. How to Operate the MiniVol
Operating the sampler involves setting up the filtration media, scheduling the run, and securing the physical placement. Step 1: Prepare the Sampling Media
Use a clean, pre-weighed 47mm filter cassette (Teflon or Quartz microfiber depending on your targeting parameter).
Attach the size-selective impactor inlet (PM10 or PM2.5 separator) to the filter holder assembly. Ensure you apply a thin layer of impaction grease to the impactor plate to eliminate particle bounce. Step 2: Set the Programmable Timer The onboard timer controls the unattended on/off routines. MiniVol TAS
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