Diesel Exhaust Scrubbers

About Exhaust Purifiers & Scrubbers

Foley Environmental's award-winning Exhaust Purifiers and Scrubbers allow you to breathe engine exhaust without any health risks.

These innovative products reduce pollutants by converting the harmful exhaust to water and carbon dioxide. Inside the canister is a honeycomb substrate coated with a small amount of precious metals where the catalytic reaction occurs. The resulting exhaust air is legal and safe to breathe. We offer these devices for both gas and diesel engines.

Yale and Hyster Forklift Co now include our Foley Environmental purifiers as standard equipment on new machines. These companies are a testimony to our effective solution to exhaust emission problems, as well as to our quick shipping.

As the only U.S. based exhaust purifier specialist we pride ourselves on shipping within 24 to 48 hours of the receipt of an order.

About Foley Environmental

Foley Environmental is a division of Foley Industrial Engines, the oldest engine distributor in North America. Our 104 years in the engine business has given us extensive knowledge of fuel and exhaust systems. This makes us the ideal supplier for your company’s needs. Foley environmental serves both the public and private sectors, with a customer base that includes Boston’s Big Dig, California public works projects, Brown University, Narragansett Electric Company, IBM, Vassar College, as well as various public works projects and companies.

Foley Environmental is different: we are a three-generation, one hundred year old family firm that wants to help.

What Exhaust Purifiers Do & How They Do It

We use catalytic exhaust technology to make the exhaust emissions safe to breathe. Each purifier houses a catalytic core, which eliminates harmful emissions by collecting diesel particles and burning off dangerous pollutants such as Carbon Monoxide (CO) and Hydrocarbons (HO). The harmful emissions of the diesel engines are converted into water (H2O) and Carbon Dioxide (CO2) which make it safe to work in close proximity with your machine. Because of this technology our scrubbers allow you to work indoors close to an engine.

These air purifiers install easily and come in different styles, depending on the application. Here in the East, purifiers really came into their own during Boston’s BIG DIG project. This was the largest public works project since the Tennessee Valley Authority and we supplied most of the purifiers used. This project would not have broken ground without some way to run diesel equipment underground.

Two Styles of Purifier Scrubbers

Clip On Style

This style is the lowest cost and easiest to install. It installs at the end of the tail pipe. We supply the purifier with the appropriately sized muffler clamp. Depending on the horsepower of the engine, it is typically the size of a coffee can. The purifier can be removed and stored when it is no longer needed, such as in a rental application. Despite its low cost, it works almost as well as the combination muffler/scrubber style discussed below.

Combination Muffler/Purifier

The other style is a combination exhaust muffler/purifier. This style is most appropriate where there is not any room at the end of the tail pipe for a clip on purifier. These applications include skid steer loader and mini-excavators. These combination muffler/purifiers are exactly the same dimensions as the OEM muffler and the installation time is similar to changing out a muffler. Typically, because of this, once installed they are not usually removed. Because they are closer to the exhaust manifold, mufflers/purifiers do work slightly better than the clip on style but can cost up to twice as much because they are both a muffler and a purifier. As a result, we sell far more clip on style scrubbers than combination muffler/scrubbers.

Keeping You Up and Running

To keep you up and running we stock here in the U.S. over 400 scrubbers, both the clip on style and the combination muffler/scrubber version. Since we are the only U.S. based exhaust purifier specialist we are able to ship these units quickly, often the same day as the order is placed, and without the customs delay and other hassles involved in shipments in from Canada.

Why Are Foley's Scrubbers Better?

Extra Platinum

Our scrubbers work at lower temperatures because we use extra platinum. The extra platinum also removes some of diesel stench from the air.


We use a coating developed by the BASF. This is the standard of the industry. Other vendors may use their own coatings to their own unpublished standards. This is a significant difference.

Torturous Cell: Longer is Better

The longer path the exhaust air must travel in the scrubber, the cleaner it gets. We have a very long set of torturous cells in our scrubbers and therefore effectively more surface area in our scrubbers.

Quick Ship

Because we are located here in the U.S. you won’t have to worry about inbound shipping delays and expenses. We can ship quickly and inexpensively.

Please call us toll free at 1.800.233.6539 with any questions. We can fax or email you detailed information. Or email Foley directly at info@FoleyEngines.com.

And after you’ve gotten the exhaust fumes taken care of, you should think of the noise. Most small diesel noise is from the air intake. We supply a combination air filter/noise reducer. This innovative device is called a Walker Airsep and it is ideal for noisy generators and other equipment. Not only does it serve as an excellent noise reducer and air filter, it also routes the unburned diesel fuel back into the oil pan via the dipstick. As a result, clouds of unburned fuel don’t form above the machine and the diesel smell is reduced.