DOP TEST: double certification for the HEPA filter of your vacuum cleaner!


Delfin has a main goal: to always guarantee the highest quality and security level in the manufacture of its vacuum cleaners. In the design phase, Delfin team balances the power of suction and the filtration efficiency of its vacuum cleaners, but always keeping in mind the air load on filter.
Since 2015, Delfin offers its customers the possibility to run the DOP test while ordering the vacuum cleaner: this test allows the client to obtain an extra certification for its vacuum cleaner filtration efficiency.

What is DOP Test?

The test is about running a flow of micro-particles of oil - medium size 0.3 micron – inside the vacuum cleaner while the machine is working. This is to measure the efficiency of the HEPA filter in holding these particles.

The test is run by an aerosol photometer, which measures the concentration of particles at both extremes of the HEPA filter installed on the vacuum cleaner. This way, it is possible to establish the precise percentage of the filtered particles.

The HEPA filter (High Efficiency Particulate Air) must guarantee a very high level of filtration: Delfin industrial vacuums are equipped only with H14 certified HEPA filters, that is a filtration of 99.995% on 0.18-micron particles.

The DOP test, an additional certification.

The DOP test is a second certification on the HEPA filer, additional to the first certificate released by the producer of the filter (which is only run on the filter).
The DOP test allows to fully guarantee the highest filtration efficiency of the absolute filter by potentially detecting any damage suffered during transport operations, handling or assembly.

The DOP test is also useful to check the correct size of the filter with respect to the vacuum cleaner on which it is installed and, consequently, that the efficiency of the filter isn’t reduced by the air load.

Therefore, this test is fundamental to guarantee the absolute efficiency and safety of the filter while using the vacuum cleaner.

Why asking for the DOP test for your industrial vacuums?

To certify the performance of HEPA filter means to guarantee workers the highest safety level and to release only pure air in the environmentwhile using the vacuum cleaner.

In which case is it highly recommended to ask for the DOP test?

The DOP test is highly suggested for those industries which have to suck toxic and fine dusts as:
- Chemical and petrochemical industries
- Pharmaceutical industries (mainly in clean rooms)
- Nuclear plants
- Asbestos
removal companies
- Construction companies
- Food industries
- Surface Treatment companies

Delfin is glad to offer the DOP test, which can be requested at the purchase of all industrial vacuums that will be equipped with a HEPA filter.

For further information about the DOP test, please contact us at +390118005500 or


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