The Venturi AV/500 and AV/1000 vacuum generating system units are particularly suitable in all hospital applications in which it is necessary to get values ??of vacuum up to -850 mbar and where a central facility of vacuum generation for suction is missing, often for technical choice. As it is well known, the physical principle called “Venturi”allows to get depression from a fluid under pressure, which is obtained, in case of these devices, using medical compressed air coming from the centralized distribution plant. Such devices are composed essentially of a brass chrome-plated body, a needle valve with vacuum adjustment knob and a vacuum gauge. The version AV/1000 fits also a quick I/0 button switch and a large gauge, while in the version AV/500 a protective silicone cover on vacuum gauge avoids damages caused by possible impacts during transport or use. Being the system working with a principle where medical air under pressure goes released to the environment, the equipment has a high efficiency silencer reducing the noise to allow an adequate level of comfort for patients and operators. The system fits a special device expressly designed and realized with an one-way safety valve, to protect the patient against accidental back pressures.