NEN EN 437 : 2003 + A1 2009

Foreword
1 Scope
2 Normative references
3 Terms and Definitions
4 Gases
   4.1 Classification
   4.2 Test gases
5 Test pressures
6 Classification of appliances
   6.1 Appliance categories
        6.1.1 General
        6.1.2 Category I
        6.1.3 Category II
        6.1.4 Category III
   6.2 Operations permitted for a change of gas or
        pressure, adjustment and regulating devices
7 Choice of test gases and test pressures
8 Marking
Annex A (normative) - Conditions for preparation of the test
                        gases
Annex B (informative) - National situations
      B.1 - General
      B.2 - Categories listed in the body of the standard
            marketed in the different countries
      B.3 - Appliance supply pressures corresponding to the
            categories given in B.2
      B.4 - Special categories marketed nationally or locally
      B.5 - Test gases and test pressures corresponding to
            the special categories given in B.4
      B.6 - Special conditions
Annex C (informative) - Guidelines for extension to other
                        categories
Annex D (informative) - National situation of countries whose
                        national bodies are CEN affiliate
      D.1 - General
      D.2 - Categories listed in the body of the standard
            marketed in the different countries
      D.3 - Supply pressures of the appliances
      D.4 - Special categories marketed nationally or locally
      D.5 - Gases and test pressures corresponding to
            the special categories given in D.4