Vehicle speeds in cities are limited and must be such as to reduce the risk of potential traffic accidents. Other measures related to traffic in urban areas include reducing noise and vibrations. One of the generally accepted and frequently implemented measures that reliably reduces vehicle speeds, thereby calming traffic, is the installation of speed bumps, which can be of various shapes and heights. In this article, it is reported on the results of measurements of vibrations transmitted to the environment caused by heavy goods vehicles when they pass over a speed bump at a speed that complies with the prescribed limit. Vibrations were measured with a seismograph and geophones for symmetrically and asymmetrically placed speed bumps. It was found that simply reducing speed does not necessarily reduce traffic pollution, such as vibrations transmitted to the environment by heavy goods vehicles driving over speed bumps. Another finding is that asymmetrically placed speed bumps cause significantly greater vibrations than symmetrically placed ones.