In the European Directive 98/34/EC a standard is defined as "the technical specification - approved by a recognised standardisation body for repeated or continuous application, with which compliance is not compulsory and which is one of the following:

• International Standard (e.g. ISO);
• European Standard (e.g. EN);
• national standard (e.g. BS in the United Kingdom, DIN in Germany, CEI or UNI in Italy, NF in France,...)".

No, standards are by definition of voluntary application. For planners, installers and users, however, the compliance of a product with the standards is the best guarantee. In fact, standards are written according to the "state of the art" of the technology in each industrial sector and accurately define quality, performance and conditions of safe use of a product.

KNX is a worldwide approved international standard for home and building control, as it is a system approved as:

- International Standard (ISO/IEC 14543-3)
- European Standard (CENELEC EN 50090 and CEN EN 13321-1)
- US Standard (ANSI/ASHRAE 135)
- Chinese Standard (GB/Z 20965)

Standards are elaborated according of the interests of the entire economic system. That is why standards offer many advantages:

• increasing the safety of products;
• providing a permanent incentive to search for the best quality;
• contributing to the reduction of production costs or dispensing service or process organization;
• encouraging economies of scale;
• facilitating compliance with European legislation on the manufacturers’ side;
• promoting interoperability of products and services;
• encouraging more competition;
• facilitating free trade in all the countries that adopt them;
• promoting safety and ecological sustainability;
• protecting the environment;
• reflecting the current stage of research and development;
• ensuring better working conditions;
• promoting a common understanding.

(source: "Le regole del gioco", © 2012 UNI - Milan)