These vortex sensors in various designs are certified according to Safety Integrity Level 2 (SIL 2). Measuring tubes and insertion probes for Ex-applications up to category 3G (VA ZG1 and VA40 ZG7) as well as for Ex-applications up to category 1G/1D (VA ZG1 Ex-d and VA40 ZG8 Ex-d) are certified according to SIL 2. Operators of process technology plants and machines must assess the risk potential for persons and the environment to minimise hazards. The Safety Integrity Level (SIL) according to IEC 61508 serves to assess the safety functions of electrical and electronic systems. When using this measuring equipment the risk of litigation is reduced to a defined low level. A hazardous operating error is either prevented or in case of occurrence securely controlled. With these vortex probes vital flow measurement in different gases and gas mixtures can be carried out. The measuring range covers pipelines with a diameter of 25mm up to chimneys with several meters in diameter while offering a very low measuring range initial value of 0.5m/s.