PREN 88-1 : DRAFT 2009

Foreword
1 Scope
2 Normative references
3 Terms and definitions
4 Classification
  4.1 Classes of control
  4.2 Groups of control
  4.3 Classes of control functions
5 Units of measurement and test conditions
6 Construction requirements
  6.1 General
  6.2 Mechanical parts of the control
       6.2.1 Appearance
       6.2.2 Holes
       6.2.3 Breather holes
       6.2.4 Test for leakage of breather holes
       6.2.5 Screwed fastenings
       6.2.6 Jointing
       6.2.7 Moving parts
       6.2.8 Sealing caps
       6.2.9 Dismantling and reassembly
       6.2.10 Adjustments
       6.2.11 Resistance to pressure
       6.2.12 Blockage of canals and orifices
       6.2.13 Signal tube connections
  6.3 Materials
       6.3.1 General material requirements
       6.3.2 Housing
       6.3.3 Test for leakage of housing after removal of
              non-metallic parts
       6.3.4 Zinc alloys
       6.3.5 Springs providing closing and/or sealing force
       6.3.6 Resistance to corrosion and surface protection
       6.3.7 Impregnation
       6.3.8 Seals for glands for moving parts
  6.4 Gas connections
       6.4.1 Making connections
       6.4.2 Connection sizes
       6.4.3 Threads
       6.4.4 Union joints
       6.4.5 Flanges
       6.4.6 Compression fittings
       6.4.7 Nipples for pressure test
       6.4.8 Strainers
  6.5 Electronic parts of the control
  6.6 Design against internal faults for the purpose of
       functional safety
7 Performance
  7.1 General
  7.2 Leak tightness
  7.3 Test for leak tightness
       7.3.1 General
       7.3.2 External leak-tightness
       7.3.3 Internal leak-tightness
       7.3.4 External leak-tightness for not combustion gas
              signal carrying compartment(s)
  7.4 Torsion and bending
  7.5 Torsion and bending tests
  7.6 Rated flow rate
  7.7 Test for rated flow
       7.7.1 Apparatus
       7.7.2 Test procedure
       7.7.3 Conversion of air flow rate
  7.8 Durability
  7.9 Performance tests for electronic controls
  7.10 Long-term performance for electronic controls
  7.11 Pressure regulator performance
       7.11.1 General
       7.11.2 General test procedure
       7.11.3 Class A pressure regulator performance
       7.11.4 Class B pressure regulator performance
       7.11.5 Class C pressure regulator performance
       7.11.6 Endurance
       7.11.7 Lock-up pressure
       7.11.8 Requirement for rendered inoperative pressure
              regulators
       7.11.9 Test for rendered inoperative pressure regulators
  7.12 Pneumatic gas/air ratio pressure regulator performance
       7.12.1 General
       7.12.2 General test procedure
       7.12.3 Control performance and stability
       7.12.4 Settling time
       7.12.5 Gas/air ratio adjustment
       7.12.6 Offset adjustment
       7.12.7 Endurance
8 EMC/Electrical requirements
  8.1 Protection against environmental influences
  8.2 Supply voltage variations below 85% of rated voltage
  8.3 Short term voltage interruptions and decreases
  8.4 Supply frequency variations
  8.5 Surge immunity test
  8.6 Electrical fast transient/burst
  8.7 Immunity to conducted disturbances
  8.8 Immunity to radiated fields
  8.9 Electrostatic discharge immunity test
  8.10 Power frequency magnetic field immunity test
  8.11 Electrical requirements
       8.11.1 General
       8.11.2 Electrical equipment
9 Marking, installation and operating instructions
  9.1 Marking
  9.2 Installation and operating instructions
  9.3 Warning notice
Annex A (informative) Gas connections in common use in the various
        countries
Annex B (informative) Leak-tightness test - volumetric method
Annex C (informative) Leak-tightness test - pressure loss method
Annex D (normative) Conversion of pressure loss into leakage rate
Annex E (normative) Electrical/electronic component fault modes
Annex F (normative) Additional requirements for safety accessories
        and pressure accessories as defined in EC Directive 97/23/EC
Annex G (normative) Materials for pressurized parts
Annex H (informative) Additional materials for pressurized parts
Annex I (normative) Requirements for controls used in DC supplied
        gas burners and gas burning appliances
Annex J (informative) Typical pressure regulators and pressure
        regulator parts
Annex K (informative) Summary of requirements and test conditions,
        and examples of performance curves for pressure regulators
Annex ZA (informative) Relationship between this European Standard
         and the Essential Requirements of EC Directive 90/396/EEC
         relating to appliances burning gaseous fuels
Bibliography