This document provides basic requirements for piston type pneumatic linear actuators for industrial valve, both double acting and single acting, used for on-off and modulating control duties. It includes criteria, method and guidelines for design, qualification, corrosion protection, control and testing. It does not apply to diaphragm actuators and to pneumatic actuators which are integral parts of control valves. Other requirements, or conditions of use, different from those indicated in this document, are subject to agreement, between the purchaser and the manufacturer/supplier, prior to order.