STD 515-0003 is a standard of the Swedish manufacturer Volvo, in which the letters identify the document as a standard of the company and the number places it in a subject range, so that documents with neighbouring numbers treat related parts of the electrical and electronic installation. The manufacturer builds both passenger cars and heavy commercial vehicles, and the two ranges have historically maintained separate bodies of standards even though they share a corporate origin, so a component qualified for one range is not automatically qualified for the other and the supplier should establish which range the engineering specification refers to. The requirement states the electromagnetic conditions applicable to a component at its mounting position and the test methods by which they are applied. The commercial vehicle range of this manufacturer is a case in point, since equipment intended for a truck is tested against levels derived from a longer service life, a larger electrical installation and a harsher operating environment than the passenger car range requires.