CSN EN ISO 22580 This document applies to the design, manufacture, installation and operation of flares for the combustion of biogas. Test methods and performance requirements are also included. Biogas systems are amongst others applied at industrial plants like food and beverage industries, waste water treatment plants, waste plants, landfill sites, small scale plants next to agricultural companies and small-scale household systems. Original English text of CSN EN Standard. The price of the Standard included all amendments and correcturs.