SP Energy Technology has many years’ experience of laboratory measurement of the performance of air filters. Performance is normally measured in accordance with EN 779, for which method SP is accredited by SWEDAC. Testing involves loading the filter with several different sizes of particles, and measuring the efficiency, pressure drop and dust holding capacity of the filter.
Does the filter maintain its performance in use? This is a relevant question, as it is important that its properties should not be substantially degraded after a period of use. We test long-term performance under actual operating conditions by SP Test Method 1937, for which we also are accredited. The test involves six months’ operation of the filter in a test rig, with efficiency and performance being constantly measured over the period.
We also perform what are known as Burst Tests, which measure the pressure drop that a filter can withstand before it fails. We test HEPA filters, too, and are accredited by SWEDAC for testing in accordance with EN 1822.
Technical resources for flexible testing
In addition to the several different test rigs available to us in our laboratories, we can also assemble special-purpose test rigs, thus enabling us to customise the test rigs to suit the requirements of different types and/or sizes of filters, and to modify the test methods to suit customers’ requirements. We can test everything from flat filter materials and bag filters to cyclone filters.
With access to a range of particle counters, we can measure particles in the size interval of 0,09 µm and upwards. Other departments within SP provide additional resources in the form of advanced measurement and characterisation of particle properties such as chemical content, size and shape. In our climate chambers, we can test products under extreme conditions of heat, cold or humidity, all in accordance with the customer’s requirements.
P-marking of filters
P-marking is a voluntary certification system for quality assurance of products. The P-marking rules specify basic requirements that filters must maintain the filter class under which they are sold, and that their efficiency will not decline drastically during their operational life. Filters are therefore tested in accordance with EN 779 in respect of pressure drop and filter class, with their long-term performance in actual operation being tested in accordance with SP Test Method 1937.
A further requirement for P-marking is that the manufacturer must have a quality management system that includes documented records of inspection results of filters and materials. In addition, SP performs annual surveillance inspection visits to inspect the company’s own systems and instructions. Samples of products are taken during these visits, and tested in accordance with EN 779.
SP Energy Technology is a Eurovent test laboratory, performing testing of air filters on behalf of the Eurovent Certification Company. Eurovent certification is a voluntary certification scheme at European level. Click the link on the right for further information on Eurovent certification.
Please contact us for further information on the services that we can provide.