MET ONE Particle Counter

What is the History of the MET ONE Particle Counter?



MET ONE Particle Counter History  Lou Petralli was the original brains and entrepreneur behind MET ONE which he founded in 1976. That fledgling business was operated out of a garage in Sunnyvale California and manufactured Meteorological instruments as well as the first MET ONE particle counter. Windspeed, wind direction, relative humidity, temperature and solar radiation were the primary products in those early years. But pretty soon the MET ONE particle counter sales became more important as high tech companies wanted to protect their mainframe computers and the pharmaceutical industry started to take off.
Lou Petralli, the founder of MET ONE and the creator of the MET ONE Particle Counter  


Where Does the Name MET ONE Come From?

According to newspaper interviews with Lou Petralli the famous name originates from an abbreviation of “METeorological” and the intent to become a number “ONE” company. The unique combination of instruments was based on the idea that he would have one market to rely on if the other market declined. However, Lou had made a good choice and in 1980, with sales growing  rapidly, he moved to L Street in Grants Pass and employed 10 people.


What Was the First MET ONE Particle Counter?

The first MET ONE particle counter was the “209” which was named after the evolving clean room standard of the day called the Fed-Std-209D. This pioneering instrument used white light from an incandescent lamp. A string of other models using similar technology quickly followed including the .3S, .3D, .5S and the 200 series.


What Were the First MET ONE Laser based Particle Counters?

1985 was a turning point for MET ONE. Growth exploded when a large contract was obtained with the Seagate the hard drive manufacturer. The L Street site was no longer able to cope with the increased production so the company moved to locally to the present facility in California Avenue. This was a purpose build plant and featured innovative geothermal heat pumps to keep the working environment at a constant temperature all year round. The heat is balanced using the groundwater in the large scenic pond which gives the site such a tranquil atmosphere. Indeed, it was apparently an early vision of Lou to avoid the “smokestack and TV antenna” skyline of the city. So, it was in such an environment that MET ONE switched from White Light to Laser light sources and the first modern particle counters were developed. These laser particle counters quickly became industry standard, being renowned accuracy, robustness and long longevity. With regular servicing and calibration some of the early models remained in service for over 20 years. Typical MET ONE particle counters from this period include the 200L, 217, 203, 227 and the .3C.


Where Does Pacific Scientific Fit in?

In January 1996 a major event occurred in the Particle Counting market. Pacific Scientific (PSI) purchased MET ONE and so was able to offer an unprecedented range of brands covering both liquid and air particle counting. The portfolio included:

  • HIAC ROYCO Liquid Particle Counters
  • HYT Specialist Air Particle Counters
  • MET ONE Air Particle Counters

Around the same time an Engineer left the company and started ARTI in Grants Pass. ARTI went on to develop both the original  PODS liquid particle counter oil contamination analysis and the first HHPC handheld air particle counter.


What about the Recent History?

MET ONE Particle Counter Factory
The California Avenue facility during the time when it was run by PSI

As this short history shows, the particle counting industry is very dynamic, being driven by individuals with a powerful vision. Many changes have taken place and this has actually helped drive the development of new and better products that fully utilize the best available technologies. So in 1998 Danaher purchased PSI…and later the MET ONE, HIAC, ANATEL and ORBISPHERE brands were united in HACHULTRA. For the first time this gave a complete offering of air and liquid particle counters, TOC monitors and ppb dissolved gas detection….the ideal combination for serving the Pharmaceutical and Electronics industries. The brand portfolio was further strengthened in 2003 when Danaher purchased ARTI and so the cycle of changes was completed.


What is Going on With MET ONE Particle Counters Today?

The MET ONE brand of particle counters continues to be developed in Grants Pass, with US and Rest of World Distribution managed by HACH and European Distribution managed by HACH LANGE. In 2012 MET ONE pioneered a new technology called the “MET ONE 3400 Embedded Secure Data Transfer” ….or Simply Paperless…for which patents are pending.


What is MET ONE Simply Paperless?

MET ONE 3400 Particle Counter - Simply Paperless  Traditional particle counters print out the results onto thermal paper and this has a number of disadvantages:

  • The paper records often have to be cut up and scanned which is time consuming
  • The paper roll can release fibres that contaminate the clean room
  • Often records have to be copied by hand into excel or other digital systems.
  • This is time consuming and prone to human error

The new patent pending technology in the latest MET ONE particle counters eliminates this process completely. Data is written directly to a PDF file using exactly the same format as the original paper printouts. This secure transfer is safe, secure and 21 CFR part 11 compliant.

 The latest MET ONE Technology – Simply Paperless!  


To find out more click on these links:

MET ONE Air Particle Counters

MET ONE 3400 Simply Paperless

MET ONE 3400 Simply Paperless on YouTube


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