According to ECHA Guidance on requirements for substances in articles

Article 3(3) of the REACH Regulation defines an article as “an object which during production is given a special shape. Surface or design which determines its function to a greater degree than its chemical composition”.

In order to determine whether or not an object fulfils the definition of an article under REACH. The object’s function and its characteristics need to be assessed. (The term “object” can in principle refer to any product in the supply chain)

• function of an object – the term “function” in the article definition should be interpreted as meaning the basic principle determining the use of the object
• shape of an object means the three-dimensional form of an object, like depth, width and height.
• surface of an object means the outermost layer of an object.
• design of an object means the arrangement of the “elements of design” in such a way as to best accomplish a particular purpose