Industrial Hygiene Report: Konform® Filter Efficiency Testing

The manufacturing of electronic devices frequently involves applying a protective coating onto electronic assemblies. Sometimes the coating is sprayed onto the assembly, sometimes it’s brushed on.

Generally, the coatings contain polymers, such as methyl ethyl ketone, and solvents, such as n-propyl acetate. Both can irritate the eyes, nose and throat. Long-term exposure is not recommended.

We tested the ability of our 30-inch wide Ductless Spray Hood [SS-330-DSH], equipped with a pre-filter, a HEPA filter, and an activated carbon filter, to contain any overspray produced by spraying conformal coating onto several printed circuit boards situated inside the hood.

We gathered pre-test and post-test data from several locations in and around the hood, following NIOSH Test Method 1450 for Esters guidelines. Then we refrigerated the samples and couriered them to HIH Laboratories, an independent industrial hygiene lab.

In general terms, HIH analysis of the test results indicate that an operator’s exposure to the substances in the coating would be much reduced using the hood and filtration configuration we tested.

To see the math, download a pdf of the test results:

More information about our Ductless Spray Hoods is at and on YouTube at

All our industrial hygiene reports are found on the Data tab of our website:

We described our chemical efficiency testing in some detail in this blog: