This European Standard defines metrological and technical requirements and tests of tyre pressure measuring instruments. Tyre pressure measuring instruments (often referred to as Tyre Pressure Gauges, [TPG]) are for the inspection of pressure and/or inspection of inflation/deflation of tyres of motor vehicles. It establishes in the context of motor vehicles tyres, the minimum characteristics of the chain of measurement of tyre pressure measuring instruments intended to increase, inspect or adjust the pressure of tyres inflated by air or nitrogen. These devices, classified in different categories, are hereinafter referred to by generic term, "tyre pressure measuring instruments". This chain of measurement consists of all the elements between the tyre valve and the display device (connector, hose, control device, measurement components, reservoir, preset device etc.). They indicate the pressure difference (pe) between the air or the nitrogen in the tyre and the atmosphere. The field of application established above can be extended to other applications where no specific standard exists. Because of the influence of tyre pressure on road safety and energy efficiency, periodical reverification is strongly advised.