The Filtration Paradox: When Less is More

Stan Lengerich, Eli Lilly and Company

Reducing particulate filtration levels on exhaust air systems can, not surprisingly, conserve energy and lower operating costs. But contrary to popular belief, it also has the potential to increase safety and decrease environmental impact. Filtration of exhaust systems for research, development, and some manufacturing facilities often default to HEPA filtration as a one-type-fits-all solution—especially in the pharmaceutical and specialty chemical industries. Selection is made intuitively, as a higher level of filtration seemingly offers a higher level of security, both for employees and for the environment. On closer examination, a lesser filter, or even no filter, may be the better choice.

An accurate evaluation of filtration requirements takes into account the capabilities of the entire airflow system and the particle size and hazard levels of substances being handled. Then risks are balanced against disadvantages of filtration types. Filtration (especially HEPA) exacts a premium toll for capital, energy, maintenance, and disposal costs. Alternatively, the result of a basic risk assessment often demonstrates health, safety, environmental, and economic advantages of reducing or eliminating filtration.

This presentation describes a data-driven approach for using risk assessment to select appropriate exhaust filtration. Selection is based on lifecycle hazard and cost analysis, which provides the basis for making fully informed decisions (rather than erroneous assumptions) that are not only justifiable, but truly sustainable.

Biography:

Stan Lengerich is a certified industrial hygienist and an engineering consultant with the Eli Lilly and Company Engineering Technology Center. He brings more than 20 years of experience to his role of providing engineering consulting to research, development, and manufacturing laboratories. Stan's primary focus at Lilly is the design, delivery, and operation of laboratory containment and ventilation systems. Currently, he is working on projects in France, Ireland, Puerto Rico, and the U.S. Stan is a voting member of the ASHRAE 110 standards committee, and he is also the lead author for the Labs21 "Best Practice Guideline" for commissioning of ventilated containment systems in the laboratory.

Back to Agenda