Filtration solutions are often deployed without accurately understanding the contamination challenges of the environment to be protected. This is usually done to either implement a solution as quickly as possible, or to minimize cost by using pre-defined and readily available off-the-shelf solutions. However, this approach neither assures an efficient contaminant removal nor does it optimize cost of ownership. An inexpensive filter changed out often may be more expensive than getting a tailored, more expensive solution that lasts much longer.

The approach promoted here is the See it. Control it. paradigm, where “seeing” means measuring the contamination first in order to characterize the environment, and “controlling” means implementing a filter solution that is tailored to that specific environment. Instead of formulating a filter solution that provides equal amounts of adsorbents for different contaminant classes, we suggest adjusting the adsor­­bents such that they match the actual environmental challenge, as determined by accurate measure­ments (Figure).

Contamination control concepts detailed in this paper are specifically for filters removing gas-phase air contami­na­tion and particles, but apply equally to any other type of filtration, such as the purification of liquids, solids or slurries.

To arrive at the best characterization of the environments to be protected, an accurate and specific measurement technique needs to be applied. For gas-phase evaluation, qualitative or semi-quantitative methods are unsuitable to do so (e.g., corrosion strips or micro balances).

To measure actual concentrations as well as contaminant identification, ISO 17025 accredited lab services should be used, which are found competent for specific analyses of spe­cific environments for specified concentration ranges. Such gas-phase contaminant concentrations can range from 100s of parts per million in odor problems to single digit parts per trillion in cleanroom environments as per ISO standard 14644-8. For particle contamination, the ...