1.1 Firing systems This Part of this European Standard specifies requirements, for oil and gas firing systems of steam boilers and hot water generators as defined in EN 12952-1. These requirements also apply to firing systems of chemical recovery boilers (black liquor boilers) with the additions and amendments specified in Annex A of this standard. NOTE 1 This standard is not applicable to coil type boilers (flash boilers/small boilers) that use burners in accordance with EN 12953-7 apply for single burner installations. 1.2 NOTE 2 This standard is not applicable to the storage of liquid fuels and to transfer stations of long-distance gas pipelines. Fuels This Part of this European Standard specifies requirements, which cover the use of liquid and gaseous fuels as defined in this standard. Fuels deviating from standardized commercially available types may require additional or alternative safety measures. For black liquor these safety measures are given in Annex A. 1.3 Operation This Part of this European Standard specifies requirements for operational equipment in clauses 4 to 8 which apply to steam boilers and hot water generators with permanent supervision by properly trained personnel familiar with the special conditions of the firing system and the type of fuel being fired.