The La Vertiente gas plant in the tropical zone of Villamontes in Bolivia supplies natural gas and stabilised condensate to the country’s national hydrocarbon company YPFB. Owned by BG Bolivia, the La Vertiente plant processes gas from the Escondido, Los Suris, Palo Marcado and La Vertiente gas fields. A recent automation upgrade project at the plant has demanded the installation of motorised valve equipment with Safety Integrity Level 2 (SIL2) certification, for which Rotork Fluid Systems has supplied a total of thirty-one spring-return failsafe quarter-turn scotch yoke pneumatic actuator packages with mechanical partial stroke test facilities. The Rotork actuators are installed on Emergency Shut Down (ESD) Valves in the most critical processing areas of the La Vertiente gas plant. Applications encompass hydrocarbon condensates and water leaving the raw gas separators, glycol and hot oil in the regenerator, natural gas throughout many of the processes including the gas inlet manifold and the power gas for the compressors. Safety Integrity Level (SIL) targets are applied to the reliability and performance of Safety Instrumented Systems (SIS) used to protect hazardous activities such as hydrocarbon refining and production. Rotork Fluid Systems is capable of providing complete SIL solutions, certified in accordance with IEC EN 61508, for final elements used in SIS. For the La Vertiente automation upgrade Rotork has supplied twenty-eight CP range and three GP range SIL2 actuated ball valve packages.