Background The most common European mining technique - longwall mining - involves the use of hydraulic roof support systems that follow the progressing excavation of the coalface. Nowadays these systems use fire-resistant hydraulic fluids (HFA) which contain chemicals that might cause irritations, are not easily biodegradable and form by-products that are suspected to be carcinogenic. The hydraulic fluids are used underground, but systems have a high leakage so that large volumes are spilled into the environment. Spills in Poland alone were estimated to be 1,000,000 tonnes per year. These spillages could end up in the groundwater and surface water systems. This could damage whole ecosystems; similar fluids used in the past - and now banned -were detected in the fatty tissue of fish found in rivers near coalmines in 1989. Before the project, Quaker Chemical B.V. had developed a first generation alternative variant of the HFA - free of diethanolamine (DEA) - that was non-irritant, more biodegradable and did not form suspected carcinogenic by-products. Production costs were expected to be the same or less than for the mainstream product. Although the laboratory tests had been positive, the new product had not yet been tried in an actual working mine to demonstrate its benefits in a genuine practical situation. Objectives The project aimed to successfully demonstrate the benefits of the first generation of environmentally friendly HFAs for mining equipment. It then sought to build on the previous work to develop a second generation variant with even greater environmental benefits. The ultimate aim of the project was to persuade conservative mining companies and authorities to change their current products for the new, more environmentally sound variants. To reach its objectives, the project identified several sub-objectives that would have to be achieved along the way. It would be essential to obtain all the necessary approvals, classifications and certificates to demonstrate that the new products are safe to use and effective and reliable in their function. The project also sought to demonstrate in a practical, real-life setting that the new products provide environmental, technical, safety, social and economic benefits and that they do not result in miners being exposed to material that is suspected to be carcinogenic. Finally, the project intended to inform, motivate and activate government bodies and mining companies to use these improved hydraulic fluid concentrates in mines across the world to reduce the strain that mines currently put on the environment. Results The project obtained all the targeted approvals and certificates for the first generation HFA. It was approved without an "irritant" user label in accordance with the European Directive 91/155/EEC and was certified as safe and reliable for use in a coal mine roof support system. A significant achievement was the successful use of this product for a year in a mine in Germany. The project was therefore able to demonstrate that the new product fulfilled its technical and safety functions effectively and reliably. The project also achieved its goals of demonstrating that working with this first generation HFA fluid does not result in exposure to material suspected to be carcinogenic and that the products have clear environmental benefits. Unfortunately, however, it was not able to demonstrate economic benefits, which turned out to be a major obstacle for the success of this product. The slightly worse antibacterial performance of the new variant HFA meant that the old one could be applied at lower concentrations and therefore more cheaply. This led to the launching customer switching back to the old product after a year. Despite this setback and subsequent delay, the second generation product has been successfully developed. It has even greater environmental benefits as it is free of DEA, mineral oil and irritant biocides, which all impact negatively on natural water supplies and local ecosystems. The demonstration of the second product is now taking place beyond the planned duration of the original project at a mine in Slovenia. The results will be presented at the European Conference on Tribology in Ljubljana in June 2007 and the work on informing, motivating and activating public bodies and mining companies will start in earnest at that point. This project has developed new and innovative environmentally-friendly products and demonstrated their benefits. Although the products are not quite ready to take over the market in the conservative mining sector, the project has generated significant advances, which lead to expect that this objective will be achieved in the near future. Once this happens, the geographical impact will be high as the product will be targeted at countries such as Germany, Poland, the USA, Australia and Russia. It has clear potential to lead to new legislation restricting the use of harmful HFA products in mining.