LAP 340 – Aerosol Particle Counter

LAP 340 – Aerosol Particle Counter

The Cleanroom Particle Counter LAP 340 is an device for measuring the number and size of particles in air streams and gaseous media according to ISO 21501-4. It is built by Klotz GmbH on behalf of Topas. The measuring system is suitable for stationary as well as mobile use. The particle analyzer is especially suitable for clean room applications which enables it to cover a wide particle size range from 0.3 µm to 10 µm and a maximum measurable particle number concentration of 980,000 particles/ft3 (35 particles/cm³), in the standard version. That opens a wide range of measuring tasks. These include monitoring and checking of clean rooms, clean benches, filter facilities in operation rooms, filling facilities in the pharmaceutical industry and separation efficiency tests of filters.

Topas offers a complete set for validation of clean rooms and safety work benches, consisting of:

  • airborne particle counter LAP 340,
  • aerosol generator ATM 226, 
  • aerosol dilution system DIL 554, and 
  • isokinetic rectangular sampling probe SYS 529.


  • Quick instrument setup
  • Portable particle counter for stationary as well as mobile use
  • Automatic calibrating function enables an easy checking and recalibration of the system
  • Connection possibilities for climate sensors (air humidity, temperature, differential pressure, flow velocity)
  • User-friendly software for measuring and archiving
  • Complies with the following standards: 
  • VDI 2083 
  • DIN 1946 
  • SWKI 99-3
  • DIN 12980 
  • DIN 12469
  • US Federal Standard 209 E
  • DIN EN ISO 14644


  • Validation and monitoring of Clean rooms and Laminar air flow boxes
  • Emission measurement (e. g. vacuum cleaner testing)
  • Fractional efficiency tests of filters and separators