tubes for the food and chemical industry EN 10365: Hot rolled steel channels, I and H sections. Dimensions and masses EN 11000–19999 EN 12102: Air conditioners, liquid chilling packages, heat pumps and dehumidifiers with electrically driven compressors for space heating and cooling - Measurement of airborne noise - Determination of the sound power level EN 12103: Resilient floor coverings - Agglomerated cork underlays - specification EN 12104: Resilient floor coverings - Cork floor tiles - Specification EN 12105: Resilient floor coverings - Determination of moisture content of agglomerated composition cork EN 12199: Resilient floor coverings. Specifications for homogeneous and heterogeneous relief rubber floor coverings EN 12221: Changing units for domestic use EN 12246: Quality classification of timber used in pallets and packaging EN 12255: Wastewater treatment plants EN 12255-1: Part 1: General construction principles EN 12255-2: Part 2: Performance requirements of raw wastewater pumping installations EN 12255-3: Part 3: Preliminary treatment EN 12255-4: Part 4: Primary settlement EN 12255-5: Part 5: Lagooning processes EN 12255-6: Part 6: Activated sludge process EN 12255-7: Part 7: Biological fixed-film reactors EN 12255-8: Part 8: Sludge treatment and storage EN 12255-9: Part 9: Odour control and ventilation EN 12255-10: Part 10: Safety principles EN 12255-11: Part 11: General data required EN 12255-12: Part 12: Control and automation EN 12255-13: Part 13: Chemical treatment - Treatment of wastewater by precipitation/flocculation EN 12255-14: Part 14: Disinfection EN 12255-15: Part 15: Measurement of the oxygen transfer in clean water in aeration tanks of activated sludge plants EN 12255-16: Part 16: Physical (mechanical) filtration EN 12277: Mountaineering and climbing harnesses EN 12281: Printing and business paper. Requirements for copy paper. EN 12345: Welding. Multilingual terms for welded joints with illustrations EN 12492: Helmets for mountaineering EN 12566: Small wastewater treatment systems for up to 50 PT EN 12566-1: Part 1: Prefabricated septic tanks EN 12566-2: Part 2: Soil infiltration systems EN 12566-3: Part 3: Packaged and/or site assembled domestic wastewater treatment plants EN 12566-4: Part 4: Septic tanks assembled in situ from prefabricated kits EN 12566-5: Part 5: Pretreated Effluent Filtration systems EN 12566-6: Part 6: Prefabricated treatment units for septic tank effluent EN 12566-7: Part 7: Prefabricated tertiary treatment units EN 12572: Artificial climbing structures EN 12600: Classification of Resistance of Glazing to Impact EN 12663: Railway applications - Structural requirements of railway vehicle bodies Part 1: Locomotives and passenger rolling stock (and alternative method for freight