Mesa Labs BGI tetraCal® Air Flow Calibrator (1.2 - 30 LPM)

NIST-Traceable Venturi Calibration Standard for Environmental & Industrial Hygiene

The BGI tetraCal® by Mesa Labs is a rugged, field-ready primary standard for auditing and calibrating particulate air samplers. Engineered for the demanding conditions of environmental monitoring networks, the tetraCal combines the aerodynamic precision of a Venturi-based system with advanced compensation sensors. This allows it to deliver precise volumetric flow, barometric pressure, and ambient temperature readings instantly, without warm-up time or complex setup.

Unlike fragile soap-film or piston flowmeters that struggle in extreme weather, the tetraCal is built to perform from -30°C to +55°C, making it the "go-to" reference instrument for EHS managers and air quality technicians verifying speciation samplers, PM2.5/PM10 monitors, and industrial hygiene pumps in the field.

Key Benefits

• All-Weather Reliability: Designed for harsh field use, the tetraCal uses no moving parts in its measurement stream and operates reliably in extreme temperatures where electronic piston meters often fail.

• Simple "Power-On" Operation: No complicated menus or programming. The device automatically detects the attached Venturi and begins displaying real-time flow, temperature, and pressure data on a continuous loop.

• Wide Dynamic Range: Capable of measuring flows from 0.1 to 30 LPM (standard model) or up to 60 LPM (Ultra model), covering the full spectrum of EPA-designated samplers, from low-flow saturation monitors to high-flow European PM standards.

• NIST-Traceable Accuracy: Every unit is calibrated in Mesa Labs’ accredited ISO 17025 laboratory, ensuring your audit data stands up to regulatory scrutiny (EPA, OSHA, EU).

• Extended Field Autonomy: Runs for over 20 hours on standard AA batteries, eliminating the need for AC power at remote background stations.

Technical Overview

The tetraCal utilizes a Venturi-based measurement principle, which creates a pressure drop proportional to the square of the flow rate. Because the Venturi geometry is fixed and unaffected by humidity or vibration, it offers superior long-term stability compared to thermal mass flow sensors.

Integrated Sensor Suite:

• Flow Measurement: Venturi differential pressure sensors tailored for specific ranges (Low, Medium, High).

• Ambient Temperature: Integrated probe measuring from -30°C to 55°C with 0.5°C precision.

• Barometric Pressure: built-in sensor measuring 400 – 800 mmHg (534 – 1066 mbar).

Data Logic:

The onboard processor continuously samples temperature and pressure to calculate Volumetric Flow (Qa) and Standard Flow (Qs) in real-time. Data can be logged internally or exported via RS-232 to the Mesa BGI Companion Software for digital audit reporting.

Typical Use Cases

• PM2.5 & PM10 Sampler Audits: Verifying the flow control of Federal Reference Method (FRM) samplers (e.g., Partisol, PQ200).

• Industrial Hygiene Surveys: Calibrating personal sampling pumps for worker exposure studies (dust, silica, lead).

• Speciation Network QA: Conducting monthly flow checks at Chemical Speciation Network (CSN) or IMPROVE sites.

• Cascade Impactor Setup: Setting precise flow rates for multi-stage particle sizing instruments in research campaigns.

Why Choose This Calibrator?

The tetraCal® eliminates the "laboratory vs. field" compromise. While laboratory piston provers offer high precision, they are delicate and cumbersome in the field. The tetraCal offers comparable NIST-traceable precision in a device that fits in a backpack and can survive a snowstorm. Its Venturi physics ensures that it remains unaffected by the vibration of running pumps or wind gusts, providing the stable, repeatable data required for regulatory compliance (QAL3/EPA audits).

Specifications

• Measured Components:

  Volumetric Air Flow, Standard Air Flow, Ambient Temperature, Barometric Pressure.

• Applications:

  Field calibration of particulate samplers, industrial hygiene pump audits, meteorological research, environmental compliance verification.

• Certifications:

  NIST-Traceable Calibration; CE Marked; Meets US EPA requirements for sampler calibration and audits (40 CFR Part 50).

• Measurement Principle:

  Venturi-based Differential Pressure (Bernoulli's Principle) with active compensation for temperature and barometric pressure.