CARB and EPA-Compliant
Diesel Particulate Filter (DPF) Systems
For more than 25 years, Rypos has engineered electrically self-regenerating aftertreatment filters that remove up to 95% of particulate matter emissions and self-clean at any exhaust temperature, including idle, with no load banks or supplemental heaters required.
Data centers, hospitals, utilities, and other operators of stationary and emergency generators rely on Rypos to maintain uptime, reduce maintenance costs, and meet EPA, CARB, and local air quality district requirements, and it’s all backed by industry-leading technical support.
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DPF technology explained
What is a DPF?
Diesel particulate filters (DPFs) are exhaust treatment systems that fit in line with an engine’s standard exhaust system. By forcing exhaust gases through filter cartridges and a diesel oxidation catalyst, a DPF captures microscopic soot and black-carbon particles before they enter the air—preventing respiratory hazards and protecting the environment.
Beyond filtration, a DPF is a compliance workhorse. Modern regulations such as EPA Tier 4 Final, CARB Level 3+ and local AQMD, set particulate-matter limits that most legacy engines cannot meet on their own. Installing a DPF enables hospitals, data centers, utilities, TRU fleets and ports to keep existing assets in service while satisfying today’s standards and tomorrow’s ESG goals.
Active vs passive regeneration DPFs
Unlike passive DPFs, active DPFs are self-cleaning. This cleaning, also known as regeneration, is automatic regardless of exhaust temperatures.
While other filter manufacturers claim to have active regeneration, Rypos’ active DPF maximizes the safety, reliability and uptime of your engines and generators. Competitor systems require additional loads on the genset and extended run times resulting in increased fuel costs for filter cleaning.
Rypos’ active DPFs efficiently burn soot accumulated in the filter at 700 oC in under 3 minutes while using less than 1% of the generator output. Heaters or load banks are not required to elevate exhaust temperatures for filter cleaning. Facility owner and operators can be confident in the availability of their emergency systems.
Passive particulate matter filters have cleaning limitations. These filters are only able to regenerate under conditions where the generator is allowed to run long enough to elevate the exhaust temperatures.
When specific exhaust temperatures are not met the filter will eventually plug up with soot and engine back pressure will increase beyond acceptable limits, leading the engine to shut down and eventually fail. Facility operators must follow passive filter service guidelines, particularly related to counting cold starts, for proper operation.
See the Rypos active DPF difference
Passive DPFs depend on sustained exhaust heat that standby generators rarely produce. Watch how Rypos uses back pressure and an electronic control signal to clean the filter cartridges automatically, at any temperature, without interrupting engine operation.
What makes Rypos active DPFs better?
Hundreds of hospitals, data centers, utilities, ports, and TRU fleets count on Rypos active DPFs to keep engines legal, reliable, and cost-efficient—because each type of filter offered is engineered for its specific application and supported by a team that has refined emissions control for more than two decades.
Regulatory Compliance
Meet or exceed EPA Tier 4, CARB Level 3+, and district-air-quality requirements without replacing your engine.
Reliable
Electric self-regeneration prevents clogging regardless of engine temperatures, cold starts, engine loads or runtime, safeguarding uptime for mission-critical operations.
Low Maintenance Costs
Reliable design contributes to Rypos’ diesel particulate filters leading the industry in lowest total cost of ownership.
Rypos in the field
25 Generators. Up to 96% Less PM Emissions.
A major data center campus in Santa Clara, California operating 25 MTU S4000 diesel generators needed a verified emissions solution that could handle the low-load standby cycles typical of emergency backup power, without adding maintenance burden or risking generator availability. Rypos active DPFs were installed across the fleet, achieving PM emission levels of 0.2 g/bhp-hr or less while maintaining full uptime and compliance with California CARB and Bay Area AQMD requirements.
Our products
Diesel particulate filters
All Rypos products are active, self-cleaning DPFs that require minimal maintenance. These energy-efficient units reduce diesel particulate matter emissions by up to 95% and carry CARB Level 3+ Verification (Marine Level 3+ pending).
ADPFs
Active DPFs for 1 MW + standby diesel gensets.
RH-DPFs
Smaller footprint units for more space-limited applications
ULETRU
CARB-verified filters for Thermo King® and Carrier® Transport Refrigeration Units (TRUs).
Custom DPFs
Engine- or package-specific designs for OEM and retrofit projects.
Tier IV
DPF-plus-SCR packages to bring older engines to full Tier 4 Final compliance.
Compliance shouldn't cost more than it has to.
Rypos emissions control specialists are standing by to help you assess your compliance timeline, compare retrofit and replacement costs, and build a case for the right solution before your next deadline.
Get free consultationProven emissions results across demanding diesel applications
> 0 %
Particulate-matter removal
0 %
Verified emissions reduction
$ 0 k
Saved per TRU compared with replacement
0 kg PM
Reduced per year, per unit
Which is right for you?
Choose your industry to see the best-fit Rypos solution.
ADPF Series
Active DPFs sized for 1 MW and above diesel gensets maintain ultra-low backpressure while eliminating up to 95 % of particulate matter—helping hospitals and data centers reach CARB Level 3+ or EPA Tier 4 regulations without engine replacement.
RH-DPF Series
Compact DPFs for rooftop enclosures and cramped generator rooms; ideal for urban facilities where space is at a premium.
Tier IV
Complete filter-plus-SCR package that upgrades legacy Tier 2/3 generators to full EPA Tier 4 Final compliance and extends asset life.
RH-DPF Series
Rugged, small-footprint filters help marine diesel gensets and propulsion engines meet CARB 3+ verification and Tier IV Final EPA compliance.
Custom DPF Solutions
Our DPF’s flexible design makes them ideal for a wide variety of engines, including specialty applications where traditional DPFs don’t fit.
RH-DPF Series
The only CARB Level 3+ verified filter for rubber-tired gantry cranes removes up to 95% of diesel particulate matter and fits tight engine bays, helping terminals hit port-air-quality milestones fast.
Custom DPF Solutions
When crane layouts don’t suit a catalog unit, we can design an active DPF footprint to match.
Testimonials
“Rypos’ support throughout the project was consistently strong and timely. The team developed and executed engineered solutions to any challenges that arose.”
Rick Elder Sr.
Technical Sales and Project Manager, Pacific Power Group
“Rypos’ product has always been ahead of everyone else. After using it for years, it’s still very stable and actually saved us money in the long run.”
Jeffery Mellow
Emergency Power Generation Specialist, Stanford University
Ready to ensure compliance for your generators?
Our emissions specialists review your generator configuration, applicable regulations, and installation requirements to identify the right DPF solution for your facility. Most consultations take less than 30 minutes. No obligation and no pressure.
More about DPFs
Frequently asked questions
Diesel Particulate Matter is a byproduct created when diesel engines combust fuel. It has harmful effects on respiratory and cardiovascular health and is second only to CO2 in increasing global warming.
CO2e (carbon dioxide equivalent) is a unit that measures the climate impact of different greenhouse gases by converting them into the amount of CO2 with the same warming effect. Particulate matter from diesel exhaust has a global warming potential (GWP) of 1588.
SLCPs are powerful climate pollutants that stay in the atmosphere for a short time, but strongly contribute to global warming. Black carbon, found in diesel exhaust, methane and HFCs are a few of the most common.
DPF stands for Diesel Particulate Filter. These filters remove harmful diesel particulate matter emitted from diesel engines, protecting the local environment and the health of area residents.
The EPA first mandated that all three-quarter-ton+ trucks install diesel particulate filters in 2008. Since then, regulations have become increasingly stringent.
Active regeneration is a process in which filter cleaning is not dependent on exhaust temperatures, engine loads, the number of cold starts, or the engine run time. Due to their independence from other factors, active regeneration systems are significantly more reliable than passive regeneration systems.
Passive regeneration is a term applied to filters that have a limited ability to self-clean or self-regenerate. Regeneration can only occur passively when specific conditions of elevated exhaust temperature are accompanied by precise NOx:PM ratios. Given the variation in load, ambient temperatures, distance from the engine, number of cold starts, and engine run time, it is impossible to guarantee filter reliability or emergency power availability with a passive system.
Active DPFs are diesel particulate filters capable of self-cleaning, also known as regenerating. These DPFs perform automatic regeneration regardless of exhaust temperatures, engine loads, the number of cold starts and engine run time.
Passive regeneration is a term used to describe filters that have a limited ability to self-clean or self-regenerate. These filters are only able to regenerate under narrow conditions with specific NOx/PM ratios when exhaust reaches elevated temperatures.
Passive systems also require routine maintenance and supervision of idle operation time, cold starts, and back pressure.
Rypos’ active DPFs are extremely efficient and reliable, requiring very little maintenance. Passive DPFs are significantly less efficient and reliable than active DPFs, requiring routine maintenance and supervision.
Yes. Our active DPF systems can be configured with selective catalytic reduction (SCR) to achieve NOx reductions of 95% or more, meeting Tier 4 standards.
Genset and RTG filters are powered when the generator is running. Rypos-supplied transformers are fed by a breaker off of the emergency distribution panel.
TRU filters are powered by a 105- or 120-amp alternator when the engine is running.
Rypos DPFs will not negatively affect engine performance. Our DPFs maintain an average back pressure well below engine manufacturers’ specification.
Rypos filters only require a very low level of maintenance. We suggest visually inspecting DPFs every 1000 hours.
Rypos filters provide sound attenuation, eliminating the need for a separate silencer for standby applications. Our filters can be mounted inside or outside of the enclosure, and we work with our vendors to ensure that the installation meets sound specifications.
Contact a Rypos emissions reduction specialist at info@rypos.com or call:
Genset Sales – 508.448.3907
TRU Sales – 508.448.3908
Service – 508.448.3906