Sampling Systems / Aerosol Substances / Dryer
ISO 14644-3

SYS 529 - Rectangular Sampling Probe

Isokinetic sampling probes are required, for example, for leakage testing of built-in filter systems in cleanrooms and cleanroom facilities. In the existing standards and guidelines, probes with rectangular cross-sections are recommended.

The Topas probes have a rectangular cross-section at the suction point, which merges steadily into a round cross-section for the hose connection. The manufacturing process guarantees a high-quality, smooth surface inside the probe, including all transitions. The constructive design of the probe is based on the international standard ISO 14644-3 as well as the VDI guideline 2083-3.

  • location-independent count rate
  • precise scanning even in filter corners
  • low scanning time due to larger probe width (transverse to the scan direction)
  • leakage testing of built-in filter systems
  • Cap
  • Cap and filter
  • Antistatic Silicone Tube

Sampling is called isokinetic if the downstream flow velocity of the filter is equal to the flow velocity at the inlet of the probe.

If the downstream flow velocity of the filter (UF), for example, is greater than the flow velocity at the probe inlet (US), part of the airflow will bypass the probe. Large particles, unlike small particles, cannot follow the change in airflow and just they are captured by the probe. The sample is fractionated and the measurement results falsified.

Consequently, it is important that the dimensions of the probe are adapted to the sampling volume flow and the down­stream velocity of the filter to ensure compliance with the isokinetic sampling.


probe housing
hose connection

anodised aluminium
stainless steel

without hose connection
with hose connection


150 mm
230 mm

weight ca. 170 g