1. General Details


    • Constant airflow maintained with ΔP across the filter up to 17″ Hg (Flow Rate Dependent)
    • Balanced, Easy to carry system
    • Flow rate indicated on rotometer, CFM or LPM
    • Rated for continuous duty
    • Low noise level
    • Minimal maintenance
    • Optional elapsed time indicator
    • All units individually calibrated and traceable to NIST

    The Model AVS-28A Portable Constant Flow Air Sampler is a continuous duty, constant flow device. It can be used with filters and cartridges in the collection of airborne contaminates, or as a regulated, positive displacement vacuum supply for continuous air monitors and stack sampling systems.

    The ability of the AVS-28A to maintain a preset sample flow rate is controlled by the unique side-mounted regulator valve. The RADēCO regulator valve is not a bypass design, and therefore the exhaust contains only sampled air. The AVS-28A has the superior ability to compensate for added P across sampling media.

    The sampling flow rate is read out on a side-mounted rotometer which measures the differential pressure across the in-line anodized aluminum venturi. All units are individuall y calibrated and traceable to NIST.

  2. Specfications

    Air Flow Rate: Adjustable from 0.5 to 3.5 CFM (15 to 100 LPM).

    Air Flow Regulation: +5% of set air flow rate up to maximum capability of pump.

    Dimensions/Weight: 12” Long x 14” Wide 9” High, (30.5 cm x 35.6 cm x 22.9 cm), 38 lbs (17.27 kg).

    Power Requirement/Cable: 115V, 60Hz, 4.6 Amps; 230V, 50hz, 2.3 Amps. Three wire, (6) six feet (10) Ten Amp rating; British and European available.

    Air Flow Indicator: Venturi mounted rotometer.

    Air Mover/Motor: Self-adjusting carbon vane type. Pump is designed for continuous operation at 26” Hg vacuum. Rated at 1/4 horsepower with thermal overload protection.

    Input Connection: 3/8” Female Quick Disconnect.

    Re-settable Elapsed Time Meter: 99999 hours and 59 minutes, pushbutton re-settable.


  3. Sample Holders Available

    Model No.



    2” diameter filter, open face


    47 mm diameter filter, open face


    2” diameter filter/RADēCO cartridge, open face


    47 mm diameter filter/RAD ēCO cartridge, open face


    2” diameter filter/RADēCO cartridge, in-line


    47 mm diameter filter/RADēCO cartridge, in-line