G 152 Sustainability Report 2016 > use of drones for inspections in chimneys, boilers and canals, to prevent the risks connected with direct access by workers to such places; > application APP5RO execution of safety measures (Five Golden Rules) in dead working must be certified through smartphone cameras sending pictures to an Enel Server via a mobile app, ensuring their compliance (1. Com pletely section the plant; 2. Make sure you are not closed in and put up warning signs; 3.