9.90110 belongs to the series of numbered test requirements of the Italian manufacturer, and a document of this type is broader than an electromagnetic compatibility requirement because it sets out the tests a component must pass across several categories of stress rather than in the electromagnetic domain alone. A component specification at this level typically covers the electrical behaviour of the unit over its operating voltage range, its behaviour under the abnormal conditions of the vehicle supply, its resistance to the climatic and mechanical environment of its mounting position, and its electromagnetic compatibility, and it directs the reader to the method documents for each. That breadth is the reason a supplier usually receives one such document together with a set of specific requirements, and it is also the reason the test programme for a component is longer than an electromagnetic assessment alone would suggest.