Harmful emissions

Diesel particulate matter (DPM)

Although there is a great deal of attention around CO2 emissions, there is another emission danger that severely affects the environment and the health and safety of those in the local area — diesel particulate matter. Its detrimental environmental effects can be calculated as a CO2 equivalent.

Vehicles and equipment powered by diesel engines account for more than two-thirds of all particulate matter emissions, and replacing these engines in the near future is not a viable option. Fortunately, these harmful particulates can be greatly reduced with Rypos’ diesel particulate filters.

Diesel particulate matter explained

What is diesel particulate matter?

  • Exhaust from diesel engines contains a mixture of gases and solid particles. Those solid particles are what make up diesel particulate matter.
  • Diesel particulate matter includes hundreds of chemical elements, including sulfates, ammonium, nitrates, elemental carbon, condensed organic compounds, carcinogenic compounds — even heavy metals such as arsenic, selenium, cadmium, and zinc.
  • Black carbon, also known as soot, is the key component of diesel particulate matter. A known carcinogen, black carbon negatively affects respiratory health and contributes to climate change.

Industry leadership

Why are Rypos particulate filters (DPFs) leading the diesel emissions control industry?

Eliminating emissions

Rypos diesel particulate filters eliminate up to 95% of the diesel particulate matter emissions contained in diesel exhaust immediately on installation, improving air quality for employees, visitors, and area residents and lowering the risk of health impacts.

Reducing effect on climate change

Rypos’ DPFs significantly reduce PM emissions, smoke, and odor in areas where filters are installed, reducing the effect on climate change with no impact on engine performance or back pressure.

Maximizing safety & reliability

Unlike other manufacturers, Rypos’ DPFs are self-cleaning via active regeneration, maximizing the safety and reliability of your diesel engines and generators while decreasing pollution exposure.


How are CO₂ (greenhouse gases) and black carbon related?

  • Due to lack of complete combustion in diesel engines, the resulting exhaust forms a mixture of gases and solid particles.
  • This mixture is comprised of CO2, carbon monoxide, volatile organic compounds, organic carbon and black carbon particles.
  • According to the CCA Coalition, black carbon has a warming impact on the climate that is 460-1,500x stronger than CO2 per unit of mass.


How is diesel particulate matter formed?

Inefficient combustion

Diesel fuel never combusts completely. This inefficient combustion creates a combination of CO2 and diesel particulate matter, including black carbon.

Vehicles and diesel-powered equipment

Vehicles and equipment powered by diesel engines account for more than two-thirds of all particulate matter emissions.

Climate impact

What is the climate impact of diesel particulate matter?

  • Black carbon emissions are second only to carbon dioxide in their climate warming impact.
  • While black carbon is short-lived with a lifetime of 4-12 days, its warming impact is 460-1,500 times higher than that of carbon dioxide. This is due to its ability to absorb incoming solar radiation and convert it into heat, effectively warming its surroundings.
  • Black carbon also reduces the surface albedo of snow and ice crystals, making them susceptible to heat and melting. When embedded in clouds, soot absorbs and dims the sunlight that reaches earth, causing changes in cloud and rainfall patterns which affect both ecosystems and human livelihoods.

Human impact

What is the human impact of diesel particulate matter?

Fine particle penetration

Fine particles classified as PM2.5 present a higher health risk due to their small size. This allows them to penetrate deep into respiratory and circulatory systems, causing damage to the lungs, heart, and brain.

Cardiovascular & respiratory illness

Diesel particulate matter causes irritation to eyes, noses, throats, and lungs, contributing to cardiovascular and respiratory illness and premature death.

Children & elderly

Individuals with preexisting respiratory conditions, children, and the elderly are the most vulnerable to diesel particulate matter. It is estimated that tens of thousands of people die prematurely each year in the US as a result of particulate pollution.

Potential carcinogen

The U.S. Environmental Protection Agency (EPA) has classified diesel exhaust as a potential human carcinogen. Studies of workers exposed to high levels of diesel exhaust demonstrated a 20 to 50 percent increase in the risk of lung cancer or mortality.

Particulate matter has been linked to:

  • Reduced lung function, pneumonia, and lung cancer
  • Respiratory diseases such as asthma, bronchitis, and emphysema
  • Irregular heartbeats, heart attacks, and cardiovascular diseases
  • Strokes


How is diesel particulate matter measured?

Particle collection filters

The most accurate, but time-consuming, method draws air onto a particle collection filter. The weight of the filter is then compared to its weight before collection. The collected particles can then be chemically analyzed.

Optical instruments

Another method uses optical instruments to examine how properties of light, including scattering, absorption, and extinction, react to the presence of particles.

Ultrafine particulates

Particulate matter can be smaller than 10 microns in diameter. Fine particulates are smaller than 2.5 microns and ultrafine particulates are smaller than 0.1 microns. Ultrafine particulates make up 80-95% of diesel soot pollution.


How to reduce diesel particulate matter?

  • The ideal way to reduce diesel particulate matter is to move away from fossil fuels and internal combustion engines, a practice known as decarbonization. Decarbonization will take many years and is currently not a broad scale option for fleets and diesel genset owners and operators.
  • A parallel strategy to decarbonization involves the immediate cutting of short-lived climate super pollutants like those found in diesel particulate matter, buying valuable time to decarbonize and mitigate the worst outcomes of climate change.
  • Rypos’ active diesel particulate filters can filter out up to 95% of diesel particulate matter emissions.

Illustrating the impact

Determining CO₂e for transport refrigeration units

Diesel combustion creates CO₂ emission equivalents

One gallon of diesel fuel weighing approx. 3.2kg combusts incompletely, producing around 10kg of CO2, plus additional CO2e from particulate matter (PM) and carbon monoxide (CO). This can add an additional 7kg of CO2e based on the emissions from a typical transport refrigeration unit (TRU).

PM and CO make up a significant portion of total TRU emissions

These additional emissions have a much greater global warming potential (GWP) than that of CO2. GWP is the heat absorbed by a greenhouse gas in the atmosphere, calculated as a multiple of the heat that would be absorbed by the same mass of carbon dioxide. GWP is 1 for CO2, while 1.6-2 for CO and 1,500 for black carbon PM.

Example of emissions impact

If a typical transport refrigeration unit (TRU) consumes 0.8 gallons of diesel per hour with an average annual usage of 2200 hours, that TRU will consume 1760 gallons of diesel and emit around 30 metric tons of CO2e/year.

Rypos DPFs reduce emissions

Adding a Rypos active diesel particulate filter (DPF) will cut the short-lived climate pollutants like black carbon by over 90% on average, resulting in a reduction of approximately 11 metric tons of CO2e/year.

That reduction is the equivalent of:

  • 2.5 gasoline-powered cars traveling 11,520 miles per year
  • 458 barbeque cylinders full of propane
  • 1.3 million smartphones charging

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Contact us

Contact us to learn more about how reducing black carbon emissions with Rypos active diesel particulate filters can help reduce global warming and improve human health and safety.