The Penmann Jargon Buster: HEPA Filtration Explained

Welcome to our jargon buster, a new semi-regular feature in which we define a few terms we use that might leave you scratching your head.

For this post: HEPA filtration

high efficiency particulate air (HEPA) filters are one of the most widely used filtration systems in the world, and you’ll find them everywhere from air hangars to food production facilities to the air conditioner in your home.

But how does it work?


HEPA works by capturing large amounts of contaminants in the air, making it ideal for work environments where even minute particles could contaminate foodstuffs or cause breathing difficulties for staff. As defined by the Institute of Environmental Sciences and Technology, a HEPA filter must capture a minimum of 99.97% of contaminants at 0.3 microns in size.

It’s difficult to imagine what these microns might look like or how many there are circulating in the air. But we’ve all seen the number of particles toing and froing through a narrow beam of light – imagine breathing that in day after day, or finding those tiny microns have ruined a day’s worth of produce.

The origins of HEPA filtration


The original HEPA filtration system was invented in the 1940s as part of the Manhattan Project (the project which eventually gave birth to the atomic bomb), with the aim of preventing the spread of radioactive contaminants.

Since then it’s moved into every facet of our daily lives – and we’ve even used it to help prevent yeast and mould contamination in our clients’ produce.

Our microbially tested filtration systems are designed with our clients’ needs in mind, and HEPA filtration is just one solution that could apply to your facility.

If you’d like to learn more about HEPA filtration, or any of our other services, please get in touch on 0113 202 7300 or email