Logo of the Physikalisch-Technische Bundesanstalt

General information on the delivery of activity standards

The Physikalisch-Technische Bundesanstalt (PTB) in Braunschweig and Berlin is the national institute for science and technology and the highest technical authority of the Federal Republic of Germany for the field of metrology and certain sectors of safety engineering.

The PTB comes under the auspices of the Federal Ministry of Economy and Labour. It meets the requirements for calibration and testing laboratories as defined in the EN ISO/IEC 17025.

It is the fundamental task of the PTB to realize and maintain the legal units in compliance with the International System of Units (SI) and to disseminate them, above all within the framework of legal and industrial metrology. The PTB thus is on top of the metrological hierarchy in Germany. Calibration certificates issued by it document that the object calibrated is traceable to national standards.

To ensure worldwide coherence of measures, the PTB cooperates with other national metrology institutes within EUROMET on the regional European level and on the international level within the framework of the Metre Convention. The aim is achieved by an intensive exchange of results of research work carried out and by comprehensive international comparison measurements.

Within the scope of the PTB's activities, the "Unit of Activity" Working Group is concerned with activity measurements and with the preparation of activity standards. Hereafter, the activity standards are described in their various forms available (solutions and solid sources).