This European Standard specifies methods for the classification and assessment of function blocks designed to operate burners and appliances burning gaseous or liquid fuels with particular regards to their fault behaviour and preventative measures.This European Standard is applicable to control function blocks, not covered by a dedicated control standard (e.g. EN 88-1:2011, EN 88-2:2007, EN 125:2010, EN 126:2012, EN 126:2012/prA1:2014, EN 161:2011+A3:2013, EN 257:2010, EN 298:2012, EN 1106:2010, EN 1643:2014, EN 1854:2010, EN 12067-2:2004, EN 16304:2013 and EN 16340:2014, EN ISO 23553-1:2014).