DVGW

The German Technical and Scientific Association for Gas and Water (Deutsche Vereinigung des Gas- und Wasserfaches e.V.)
The purpose of the organization is to promote the gas and water sector with regard to technical and technical-scientific matters, while giving special attention to safety and environmental concerns. The DVGW certification centre checks and certifies gas and water-related technical products, enterprises, management systems and official experts. The basis for this work is DVGW’s own set of rules as well as nationally and internationally recognized guidelines. The DVGW certification centre provides manufacturers the means (conformity certificates) to verify to their customers that the current level of technology has been adhered to.
See also: www.dvgw.de