Olores.org Newsletter December 2025

   As 2025 comes to a close, all of us at Olores.org would like to extend our warmest wishes for a joyful holiday season and a bright start to the new year. This is a time to pause, reflect, and celebrate — to look back with gratitude and look forward with hope.

   Whether you’re spending these days surrounded by loved ones, traveling, or taking a well‑deserved moment of rest, we hope that peace, happiness, and inspiration fill your days.

  Another year has come to an end, and once again, we bring you our summary of what’s happened in the world of odours during 2025. Each year, the number of posts we publish continues to grow, which makes it increasingly challenging to put together a summary that people will actually read to the end. Still, this moment is reserved for those of you who are truly passionate and eager to keep up with everything that’s been happening in the field of odours.

  Before we dive into the review, there are two things I’d like to mention. First, the domain Olores.org was registered back in 2005—meaning we’ve now been sharing news and insights on odours for 20 years. Time really does fly! We’re all a little older and, hopefully, a little wiser. Our first monthly newsletter in English was sent 12 years ago, and we’re proud of how far we’ve come.

  Secondly, we’d like to remind you that we are an odour consultancy company that one day decided to share our knowledge—and that of others—freely with the community. Occasionally, companies have sponsored this website as a token of appreciation, which we’ve always valued. However, it’s been quite some time since we last had a sponsor. We continue doing this purely out of passion, but as a for-profit company, Olores.org doesn’t generate income for us. If you’ve enjoyed our work over the years, please consider advertising with us to help support 20 years of dedication to the odour field. Thank you!

   Now, let’s get started with our review of this year’s highlights.

   The UK Environment Agency has replaced its long‑standing H4 odour guidance last updated in 2009 with a new GOV.UK guidance hub titled “Odour management: comply with your environmental permit,” a change that removes many of H4’s previously detailed technical prescriptions and moves regulation toward demonstrating compliance with best available techniques (BAT) and appropriate measures. In addition, the odour limits are gone. 

   The H4 document (now withdrawn) used to provide extensive technical guidance, including benchmarked odour assessment approaches, structured testing and recommended modelling practice. The first H4 Horizontal Guidance for Odour was published in 2002 and included the first odour limits set in the UK. In 2009 this Guidance was updated but the odour limits based on percentiles 98 were left untouched. Sixteen years later the Agency has concluded that the H4 format was out of date and replaced it with a new online guidance which is shorter (no pdf here) and more principle‑based.

   The Clean Air Society of Australia and New Zealand (CASANZ) is organizing its 2026 conference, accessible at https://tsevents-2026-casanz-conference.eventsair.site, bringing together experts in air quality and odour control from around the world. This event promises in-depth discussions on odour dispersion modeling, source characterization, innovative mitigation technologies, and regulatory updates, much like the focused sessions at past OLORES conferences that advanced practical solutions for industry and communities.

   Last year, the 27th CASANZ International Clean Air and Environment Conference, held alongside the 10th Odours and Air Emissions Conference, concluded successfully. Organised by the Clean Air Society of Australia and New Zealand (CASANZ) in collaboration with the International Water Association (IWA), the event featured over 110 presentations covering a wide range of topics in air quality and odour management through parallel sessions. Once again, CASANZ is back in action with another new conference but the same format than in Hobart.

  The draft of the German standard VDI 3940 Part 6:2025-07 was published in July this year. This text addresses the determination of disgusting and nauseating odours. This standard is currently in draft stage, accepting comments from interested parties.

  During the last biennial conference of the Association of German Engineers (VDI)on odour management in the environment, held in Salzburg, several interesting presentations took place. One of them moved away from the concept of odour as being “only an annoyance”. In fact, this presentation, given by Dr Kirsten Sucker, addressed the question of whether an odour “merely” constitutes a considerable nuisance or whether it is so disgusting and nauseating that it should be classified as a harmful effect on the environment. But what exactly is the difference and how can this be determined?

   The new amendment of the existing regulation on TRS for pulp mills expands requirements for pulp mills in Chile. Currently, there are seven such facilities in this country, located from the Maule Region to Los Ríos.

   The Ministry of the Environment reported that the update of the Odour Emission Regulation for Pulp Mills has been published in the Official Gazette today, modernising the standards applicable to Kraft or sulphate pulp production, whose processes can generate odours that affect the quality of life of nearby communities.

   Olfasense GmbH invites industry professionals to mark April 28-29, 2026, for its annual Odour Workshop on Product & Material Testing at their laboratory facilities in Kiel, Germany. This event targets sectors involved in odour evaluation, offering presentations by specialists, hands-on lab sessions on sensory and molecular techniques, and one-on-one discussions.

   Attendees will explore odour measurement methods, including GC-MS, GC-Sniffing, and panel training, building on successful prior editions like the 2024 workshop featuring keynote speakers and practical sessions on sample preparation and indoor evaluations. Limited to 35 participants for optimal interaction, the programme details are forthcoming, with early bird registration available now.

   The kick-off meeting for drawing up the Best Available Techniques REFerence document for Landfills (LAN BREF) took place as a hybrid event from 6 to 9 October 2025, gathering 166 experts—82 in person and 84 online—representing EU Member States, Norway, industry, environmental NGOs, the European Chemicals Agency (ECHA), and European Commission services. This meeting launched the process of developing a standalone BAT reference document specifically for landfills, reflecting their importance and complexity within waste management.

   On 17 August 2025, the European Commission published the Decision establishing the BAT conclusions for Waste Treatment (WT) in the Official Journal of the EU. This BREF focuses on waste treatment technologies but intentionally left landfills out of its scope. The decision to exclude landfills was made deliberately to allow for a dedicated and more comprehensive BAT document addressing landfill-specific issues, which is now being developed through the ongoing LAN BREF process.

  The Ministry of the Environment of Chile celebrated Odour/Odor Day (2 December) with a special seminar held both onsite and broadcast online via YouTube. The seminar was organised by the Department of Noise, Light and Odours of the Ministry of the Environment (MMA) within the framework of the Strategy for Odour Management in Chile. Its aim was to provide an informative space for dialogue about the progress and challenges in environmental odour management in the country.

  A few years ago, the AMIGO Society approved the establishment of the 2nd of December as “Odour/Odor Day”. The idea was to encourage any organisation to plan activities and initiatives to celebrate this day. In 2025, several regulatory agencies met in Chile to discuss odour regulation. Representatives from various agencies related to the environment, health, and wastewater management shared different approaches adopted in the country to address odour impacts.