What Products Need CE Marking?
CE marking is mandatory for products that fall under one of the 25 CE Directives or Regulations. When a product is not covered by one of these Directives or Regulations, affixing the CE mark is forbidden.
Often, more than one Directive or Regulation may apply to a product. See here for the full list of Directives and Regulations that are part of CE Marking.
Google the ones that might be applicable to your product and visit the official eur-lex.europa.eu site. There you can find the Directive or Regulation. To determine if a Directive or Regulation applies to a product, consult the scope and the definitions of the directive. Also, check the exceptions that are not covered by the directive to find out if your product is excluded.