The purpose of this standard is to establish the essential technical requirements for the design, construction, testing, operation, maintenance and periodic inspections of plants intended for storage, transfer and filling of liquefied petroleum gases. This standard is applicable to all plants intended for: storage, transfer and filling of liquefied petroleum gases. Regarding the filling operation it applies to LPG cylinders defined on Art. 3 of Reglamento técnico de distribución y utilización de combustibles gaseosos sanctioned by Real Decreto 919/2006 de 28 de Julio , excluding LPG cylinders intended for other applications such as: cylinders for refrigerating gases or mobile tanks for hot-air balloons.