This European Standard specifies the general requirements and the constructional and operating characteristics relating to safety ), marking, and the associated test methods for gas heated commercial catering and bakery appliances. The specific requirements are given in Part 2. Requirements on materials and parts in contact with food and other sanitary aspects are given in Part 3. Only appliances of types A1, A2, A3, B1 and B2, as defined in Clause 4, are considered in this European Standard. This European Standard applies to all professional cooking and bakery appliances using gas for preparing food and drink. Only the net calorific value (Hi) and net Wobbe number (Wi) are used. Annex C, informative, lists the main types of equipment entering into the field of application of this European Standard. NOTE – This European Standard does not deal with rational use of energy. This aspect is mentioned in 6.10 only for the coherency with the associated Part 2 (clauses numbering) and to mention that if no Part 2 exists for a specific product, rational use of energy has however to be considered.