ICS Triplex has developed a hard- and software package for checking safety and shutdown valves without disrupting production in petrochemical and other critical safety plants. The idea behind the valve test package is to partial stroke the valve to check that it is not stuck in the open position and to automate this testing using only the standard ESD system components. Valves and their actuators are the cause of most dangerous failure in process plants, being prone to blockage and corrosion or sticking of their moving parts. Because the procedure does not require the plant to be shutdown it can be performed regularly, with a consequent dramatic improvement in process safety. The relevant standard, IEC61508, now specifies that safety shutdown valves are included in the assessment of the process protection systems. However, operating valves periodically to test them can be highly undesirable because of the loss of production. The ICS Triplex package checks the movement of the valve after only a few percent of its travel, before returning to the open position. It satisfies the IEC61508 requirements and confirms the performance of the valve without process interruption.