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Into the Future with Metrology - The Challenges of Our Environment and Climate


Too bright and too loud

Light pollution
Light pollution in Europe at night (Fig.: NASA Earth Observatory / NOAA NGDC)

"Light pollution" does not mean that the light is dirty, but that artificial light sources are making the night sky brighter and brighter. This leads to an unnecessary waste of energy and disturbs the day/night rhythm of living beings; moreover, there are only very few truly dark places left on Earth that are suitable for astronomical research. Much light pollution comes from poorly designed or inefficient light sources. PTB is active in the characterization of energy-efficient light sources. There are no generally valid regulations for the limitation of light immissions, which is also due to the fact that neither a binding measurand nor a traceable measurement technique for the quantitative determination of light pollution exists. PTB is working on advancing metrology and legislation in this field.

Noise is a significant environmental factor. The World Health Organization classifies noise as one of the leading health risks that are due to the environment. To combat noise, it must be quantified on site. This requires measuring instruments that provide accurate, reliable results that are traceable to national standards. PTB offers comprehensive services in the field of calibration of microphones, sound level meters and additional equipment. The type approval of sound measuring instruments ensures confidence in a quantitative analysis. At the same time, PTB conducts research on infrasound, which emanates, for example, from wind turbines, and on airborne ultrasound. Here, in addition to the development of new measurement and calibration methods, the aim is to better understand how infrared and ultrasound are perceived.

Participating departments

Opens internal link in current window4.1 Photometry and Spectroradiometry

Opens internal link in current window1.6 Sound