Laboratory anemometers: how can air velocity and airflow rate be measured for airflow control?

Essential for airflow testing and balancing, the anemometer measures air velocity and calculates volumetric flow rate to qualify microbiological safety cabinets, fume cupboards, cleanrooms and HVAC systems. In the laboratory it safeguards sterile processes, checks face velocities and system balancing, and documents your qualifications and regulatory maintenance. Hot-wire or vane technologies cover every application, with data logging, telescopic probes and ISO 17025 calibrations for flawless traceability. High resolution at low velocities, temperature compensation and connectivity deliver reliable, repeatable measurements, at the bench or on site.

What types of anemometers are there, and how do you choose the right one?

• Hot-wire / thermal anemometer: a heated micro-probe measures heat loss caused by the airflow. Ultra-sensitive at low velocities and in laminar regimes (cleanrooms, microbiological safety cabinets, laminar flow cabinets). Delicate and handling-critical, yet the reference for airflow R&D.

• Vane anemometer: a rotor measures the average velocity. Robust, simple, and ideal for grilles, diffusers, filters, and flow cones. Less accurate in high turbulence or at very low speed.

Selection criteria: range (e.g. 0.01–50 m/s), accuracy (as % of reading), resolution, response time, T/RH compensation, probe type (straight, angled, mini-probe, telescopic), volumetric flow calculation with area input, data logging and connectivity (Bluetooth, export), ruggedness (IP rating, materials), and traceable calibration. For regulatory checks (ISO 14644, EN 14175, EN 12469), favour ISO 17025 calibration certificates and suitable accessories (cones for diffusers, poles for ducts).

Quick comparison:

Type	Principle	Applications
Hot-wire	Cooling of a heated wire	Laminar flow, low velocities, R&D
Vane	Rotation proportional to velocity	Grilles, filters, flow cones, HVAC

Best practice: respect probe orientation, allow the reading to stabilise, take area-averaged measurements, and protect hot-wire probes from dust and impacts.

In which application areas is an anemometer used?

Life sciences / cleanrooms : qualification of laminar flow cabinets, biological safety cabinets (BSCs), and unidirectional airflow velocity monitoring (ISO 14644).

Pharmaceutical & cosmetics : HVAC qualification, system air balancing, filter integrity and terminal grille checks in classified areas.

Food & beverage : control of packaging environments, cooling tunnels, hygienic compliance checks.

Chemistry & safety : verification of fume cupboard face velocities (EN 14175) and local exhaust capture.

Environment & HSE : ventilation diagnostics, at-source capture, energy audits.

R&D / education : flow studies, airflow prototypes, testing on porous materials.

Maintenance & facility management : commissioning and optimisation, troubleshooting, regulatory documentation with full traceability.

The different types of anemometer available

Anemometer

Frequently asked questions about laboratory anemometers

Which technology should you choose for very low velocities?
The hot-wire offers the highest sensitivity and a short response time, ideal for laminar flows and ISO clean zones, with traceable calibration.

Vane or hot-wire for measuring a supply grille?
The vane is robust and provides good area averaging. Hot-wire is more accurate but sensitive to orientation and turbulence.

How to convert a velocity into volumetric flow rate?
Enter the opening area (m²): Flow rate = velocity (m/s) × area. Use a cone or flow hood to stabilise the flow over a diffuser.

How often should an anemometer be calibrated?
In general, every 12 months or according to your quality requirements. Prefer ISO 17025 calibration certificates.

What precautions for a hot-wire probe?
Avoid shocks, dust and solvents. Store it protected, stabilise the flow and align the probe to minimise errors.