History of product testing

Created 17 October 2023

Testing has always been crucial to the success of every air filter

Rigorous testing of a product during its development phase is ultimately about being able to guarantee a certain level of performance. This is, of course, also true for high quality air filters like Camfil's. And the way these products are tested has always been changing and evolving.

If you look at the history of a company like Camfil, the testing of new filter products has
always been a central part of the business.

 

It was evident already in Camfil’s second year of operation, in 1964. Starting production
of the first HEPA filters for the Swedish nuclear power industry meant having to invest in
advanced testing equipment. All with the purpose of being able to individually test the
integrity of each filter to ensure compliance with the norms of the International Atomic
Energy Agency (IAEA). 

 

Camfil’s test rig was the first advanced testing equipment for HEPA filters in Europe.
It made it possible to guarantee a filter efficiency of 99.97 percent on particles 0.3 microns
in size. The aerosol test process was the Dispersed Oil Particulate (DOP) test, which is
still in use today.  

 

The use of aerosols for testing air filters began during World War II, when the allied forces
sought ways to protect soldiers from chemical fogs or other toxic warfare. Leading researchers
chose dioctyl phthalate (DOP) as their testing aerosol for its ability to produce a narrow
distribution of particle sizes. They also worked from the theory that, for air filters at that time,
the focus should be on capturing particles approximately 0.3 microns in size. 

 

DOP and other clear liquid aerosols remained the preferred choice, even though attempts
were made to use solids such as sulfur and stearic pipes. But they did not work as well since
they caused testing equipment to be clogged and contaminated, leading to too much variability
in the test results. 

Highly accurate field simulations


Anders Sundvik is Vice President of R&D at Camfil and has been a key figure in Camfil’s product development for more than twenty years. 

 

He describes testing as having gone from simulations of real situations using aerosols in lab environments, that were not always quite real enough, to field simulations that are highly accurate in simulating real environments and conditions.

The first version of the mobile Camfield test labs that Camfil has now, was stationary and built 
in Borås, in Sweden, by RISE, an independent, state-owned research institute. At that facility, 
filters could be tested under real-world conditions. The problem, however, was that the tests 
were not done continuously, only every other month, and only in Borås. 

 

“It is not optimal to only test filters in one location that has one type of climate. When developing 
new products, you need to test them in various locations with different air volume, humidity, 
temperature, air pollution levels, etc.”

 

Nowadays, says Anders Sundvik, Camfil has several state-of-the-art mobile Camfield Laboratories, 
where filter performance can be tested in any chosen location under real operating conditions, 
while the results are continuously monitored and evaluated remotely in real time. “This allows us 
to collect test data about the filter over its whole lifetime.”

How LCA helps the customer


Anders Sundvik became Vice President of R&D in 2010. Camfil has since gone from a technology 
driven development culture to a more customer-centric approach. 

 

One example of this, he says, is Camfil’s software for Life Cycle Cost Analysis (LCA). 

 

“The LCA technology is in large part made possible thanks to the data we collect during the 
development phase of our filters, which includes the testing we do in the Camfield labs around 
the world.”

 

The data from the field tests also helps Camfil’s R&D team to better interpret tests that are 
performed in the lab and to show customers highly accurate scenarios via the LCA tool. 

 

“We have used the test data to create algorithms that enables us to simulate real-world conditions 
within the LCA software. This makes it possible to accurately predict how the product will work for 
our customers; how various filter materials will perform, different outcomes when choosing one 
product configuration instead of another, and so on.”

 

Anders Sundvik underlines that it is not enough for Camfil’s customers to only know the cost of 
the actual air filter. The great benefit of Camfil’s LCA tool, is that it provides a range of other cost 
variables over a filter’s lifetime, such as filter efficiency, how long the filter will last, how much it 
will cost to change and dispose of the filter and the largest expense, which is energy usage.

 

“What this means is that the data generated while testing our filters during the development phase 
makes it possible for our LCA tool to help our customers optimise their power output, minimise their 
maintenance, reduce their fuel costs and CO2 emissions - and increase their profitability,” 
concludes Anders Sundvik.