LAMINAR AIRFLOW

PRINCIPLES

Laminar Airflow Principles

Why Use Laminar Airflow?

Laminar airflow systems are designed to control airborne contamination such as:

Dust
Visible and invisible particles
Bio-contaminants (bacteria, fungi, viruses, etc.)

They are widely used across industrial, hospital, and laboratory environments, and are installed as close as possible to the process area whether in an industrial workspace or a controlled environment (cleanroom or grey room).

What Is Laminar Airflow?

A laminar airflow is a unidirectional, non-turbulent flow of air in which air velocity remains uniform across the entire blowing surface.

It is defined by the following velocity criteria:

Vavg – 20% ≤ Vindividual ≤ Vavg + 20%

The typical target airflow velocity is 0.45 m/s.

Laminar airflow systems are tested in accordance with ISO 14644-3, creating a piston effect that pushes contaminants away from the protected area unlike turbulent airflow, which increases the risk of cross-contamination.

Our Laminar Airflow and Air Shower Solutions

Laminar Airflow Ceiling

Sampling Station

Fan Filter Unit (FFU)

Air Shower

Modul’Air

Weighing Booth

FFU – Modul’ air

Our Laminar Airflow and Air Shower Solutions

Laminar Airflow Ceiling

Sampling Station

Fan Filter Unit (FFU)

Air Shower

Modul’Air

Weighing Booth

FFU – Modul’ air

TECHNICAL CHARACTERISTICS

Laminar Airflow Behavior

The air exiting a T.H.E. filter (HEPA or ULPA) can vary in velocity depending on fan adjustment.

Turbulent Flow:

If v < 0.35 m/s → air velocity is too low → flow becomes turbulent.
If v > 0.55 m/s → air velocity is too high → flow becomes turbulent.

Laminar Flow:

When 0.35 m/s < v < 0.55 m/s, airflow remains laminar and stable.

Key Properties of Laminar Airflow

Air streams move in a unidirectional path (piston effect).
Air layers flow smoothly and without disruption.
Air can bypass minor obstacles and re-form downstream, maintaining clean airflow.

Laminar Airflow Rate

With an airflow velocity of 0.45 m/s, and assuming a filtration surface of 1 m²,
the air volume processed by one LAF unit is approximately 1,620 m³/h per m² of filter surface.

Air Renewal Rate

For a Laminar Airflow Filter (LAF) operating at 0.45 m/s, protecting a process area located 1 meter below:

The protected volume is 1 m³.
The air renewal rate (TR/h) is 1,620 times per hour.

This means the protected volume’s air is completely renewed every 2.2 seconds, ensuring an ultra-clean environment and maximum protection of your process.