What is accessa?

The Association for the Catalytic Control of Emissions from Stationary Sources to Air. We formed in 2016 to promote the technical and economic viability of using catalytic after-treatment to reduce harmful discharges to the air from large fixed (or stationary) industrial sources such as factories and power stations.


What type of organisation is and who runs it?

We are a non-profit trade group based in Brussels and administered by leaders in the field of emissions control: Gore, Johnson Matthey, Umicore and Clariant.


What is your mission?

To promote the technical and economic viability of using catalytic controls to reduce emissions from large fixed industrial sources.  


What is catalytic after-treatment?

Catalytic after-treatment works in a similar way to catalytic converters in motor vehicles, but on an industrial scale. Passing the gasses given off by industrial activities through an after-treatment process means the pollutants can be neutralised by more than 95% (and often up to 100%) - thus rendering them virtually harmless when they are released into the atmosphere.


What is a stationary source?

Stationary sources of emission are large fixed industrial locations as opposed to mobile sources, such vehicles, aviation, and shipping. In fact, transportation only represents 15% of greenhouse gases, whilst industry and energy generation cause 58% of global greenhouse gas emissions1. The main stationary emissions sources are: Energy Generation; Waste Incineration/Biomass; Minerals; Metals; Industrial Manufacturing; Food and Drink; Wood Pulp and Paper - with each sector having several sub-categories covering dozens of industries. Each industry gives off different harmful emissions which may require the kind of specialized mitigation our partner companies manufacture.


Why is your work necessary?

While the problems of emissions from vehicles are widely known there are many other dangerous chemical emissions from large stationary sources including: Nitrogen Oxides, Carbon Monoxide, Volatile organic compounds (VOCs) and hazardous air pollutants (HAPs), Methane, Ammonia, and Mercury. Industrial facilities - and the exhaust gases they give off - are much less controlled by government mandates yet are just as harmful as those given off by transportation2. Their effect on the environment damages human health from polluted air and contributes to climate change. Non-CO2 emissions represent over 25% of total pollutants, predicted to rise to 27% by 2030.3


  • The USA Environmental Protection Agency (EPA) has identified six pollutants as “criteria” air pollutants because it regulates them by developing human health-based and/or environmentally-based criteria (science-based guidelines) for setting permissible levels. These six pollutants are carbon monoxide, lead, nitrogen oxides, ground-level ozone, particle pollution (often referred to as particulate matter), and sulphur oxides.
  • 96% of Europe’s urban population is exposed to fine particulate matter above the health-based guidelines set by the World Health Organization (WHO)
  • WHO data show that 99% of global population breathes air that exceeds WHO guideline limits. Air quality is closely linked to the earth’s climate and ecosystems globally. Many of the causes of air pollution (i.e. combustion of fossil fuels) are also sources of greenhouse gas emissions. Policies to reduce air pollution offer a win-win strategy for both climate and health, lowering the burden of disease attributable to air pollution, as well as contributing to the near- and long-term mitigation of climate change.


How do you work?

We work globally with regulators, non-governmental organizations and others to advocate the development, demonstration and deployment of cost-effective emissions solutions. Our work consists of three core activities:

  • Engaging with the European Union industry regulation stakeholders to inform and demonstrate what is technically possible regarding emissions (EU Transparency Register number 490092847162-43)
  • Talking directly with non-EU countries to inform and demonstrate what is technically possible regarding emissions and encourage implementation/installation
  • Informing and educating the media and public on the dangers of emissions (particularly non- CO2 related) and how catalytic filters can have a positive impact on health and the environment


What is your end goal?

Our mission is to improve the air we breathe by using advanced technology to control emissions from power stations and industry, with the end goal of the same level of awareness and implementation of catalytic controls for industry as there currently are for transport.


How dangerous is the pollution you are trying to mitigate?

A study published in 2022 by the renowned UK medical journal, The Lancet 4 reports “Air pollution causes over 6∙5 million deaths each year globally, and this number is increasing… Lead and other chemicals are responsible for 1∙8 million deaths each year globally…. Over 200 chemicals, including lead, methylmercury, polychlorinated biphenyls, arsenic, organochlorine and organophosphate pesticides, organic solvents, and brominated flame retardants are neurotoxic to humans, and many of these chemicals are widespread in the modern environment”. Many of these emissions are not currently effectively controlled or mitigated, yet catalytic after-treatment can remove over 95% of harmful chemicals from stationary sources. Added to that is the contribution of greenhouse gases towards climate change, which affects human health as well as the environment.6


How do you quantify the cost of pollution?

The total cost to society in terms of quality of life, medical costs, life expectancy, loss of productivity, and the effect on nature and climate is almost impossible to quantify. To use the UK as an example, air pollution is responsible for an estimated 28,000 to 36,000 excess deaths a year, with just the health costs estimated to be between £8.5 billion and £20.2 billion.6


What is the cost of installing catalytic controls and does this lead to increased consumer costs?

While there is an upfront cost to installing this technology, the end results to industry, the environment and health are manifold. When emissions are regulated and governments encourage the use of catalytic systems the cost can be minimal or even neutral. For example, in France, operators of Waste Incinerators receive tax rebates when they reduce emissions of pollutants, such as Nitrogen Oxides (NOx) which are incredibly harmful. These rebates are high enough to pay for the entire additional or upgraded abatement technique. At accessa we believe that the majority of the French waste incinerators can make use of this incentive. In some cases the cost/benefit analysis can show a 2000% ROI on implementation when all facts are considered.


Why are non-CO2 emissions less regulated if they are so critical?

Most of us drive cars and take flights, and so it is easier for people to understand the environmental impact of our actions and measure the effects of mitigation. Since there are so many types of industrial activity and many different toxins, it’s incredibly hard to measure and control the emissions that each one gives off. In many cases measurement and reporting is not strictly enforced or measured accurately. We applaud the work environmental organizations and governments have done to mitigate CO2 but there are so many more dangerous pollutants coming from millions of facilities - often very close to where we live. These pollutants can be much more harmful than CO2 and last longer in the atmosphere7. We hope our work will raise awareness of the impact these can have and lead to the implementation of better standards and controls.


Are there any after-products or residue to dispose of in the process?

Catalytic treatment neutralises many poisonous chemicals from emissions such as waste gases given off by industrial facilities in the manufacturing process, energy generation or incineration. In most cases there are no or virtually no by-products from the catalytic process. Where any pollutants are trapped rather than destroyed, they can be disposed of safely rather than released in the air.


Are there any chemicals needed in the process?

Other than some adsorptive techniques, catalytic treatment does not move a pollutant from one media (e.g. air) to another (e.g. wastewater), but destroys the toxins in the process. In many cases no additive or chemical is needed at all, in others a small amount of reagent such as a natural nitrogen compound like ammonia or urea is added (and almost fully consumed) to allow complete destruction of the toxins.


How successful have you been?

At accessa we believe our partner companies have reduced approximately 20% of total stationary pollutants in the past five years and we hope to achieve much more with greater awareness and implementation. This is equivalent to millions of tonnes of poisonous emissions.


What can people do to encourage use of this technology?

Most of us live within walking distance of many stationary sources of pollution – it’s not just large out-of-town industrial estates. Such emissions are notoriously hard to measure and the harm is difficult to totally quantify when you consider such effects as the environment or human health. Even if you always recycle, some of your refuse may end up as landfill or being incinerated, emitting unregulated poisonous chemicals, when there is actually great potential for capturing pollutants whilst generating energy through Waste-To-Energy plants fitted with catalytic controls. We hope our work will encourage industry, governments, and the general public to learn more about the industries in their local areas and to check for any pollutants which are currently not legally required to be mitigated. Your local government may be a good source of information plus those listed on our Resources page.



1 (page 9, para 40)