NEN EN 777-4 : 2009

Foreword
1 Scope
2 Normative References
3 Definitions
  3.1 System and its constituent parts
  3.2 Adjusting, control and safety devices
  3.3 Operation of the system
  3.4 Gases
  3.5 Conditions of operation and measurement
  3.6 Country of destination
4 Classification of Systems
  4.1 Classification according to the nature of the gases
      used (categories)
  4.2 Classification according to the gases capable of
      being used
  4.3 Classification according to the mode of evacuation of
      the combustion products
5 Constructional Requirements
  5.1 General
  5.2 Requirements for adjusting, control and safety devices
  5.3 Ignition devices
  5.4 Main burners
  5.5 Pressure test points
  5.6 Injectors
6 Operational Requirements
  6.1 Soundness
  6.2 Heat inputs
  6.3 Limiting temperatures
  6.4 Ignition, cross-lighting and flame stability
  6.5 Pressure governor
  6.6 Combustion
  6.7 Prolonged performance
  6.8 Measurement of oxides of Nitrogen, NO[x]
7 Test methods
  7.1 General
  7.2 Construction and design
  7.3 Safety of operation
8 Marking and instructions
  8.1 Marking of the system and the packaging
  8.2 Instructions
  8.3 Presentation
Annex A (informative) System H
Annex B (informative) National situations
Annex C (informative) Equivalence rules
Annex D (informative) Calculation of the mass flow rate
        of flue gases
Annex E (informative) Identification of the type of gas
        in use in the various countries
Annex F (normative) Special national conditions
Annex G (informative) Example of calculation of the
        weighting factors for a system with several
        rates
Annex H (informative) Calculations of conversions of NO[x]
Annex I (informative) National situations of countries
        whose national bodies are CEN associate members
Annex ZA (informative) Clauses of this European Standard
         addressing essential requirements or other
         provisions of EU Directives
Bibliography

Defines the requirements and test methods for the construction, safety, classification and marking of non-domestic gas-fired overhead radiant tube systems incorporating two or more burner units with each burner under the control of an automatic burner control system, and operated by a single fan providing a single flue outlet, called system H and referred to in the body of the text as the 'system'.