I.S. 645:1983

National foreword
Brief history
1 General
  1.1 Scope
  1.2 Field of application
  1.3 Terminology
  1.4 Classification
2 Constructional characteristics
  2.1 General
  2.2 Special requirements for certain parts
3 Performance characteristics
  3.1 Soundness
  3.2 Obtaining the nominal rate and nominal output
  3.3 Performance safety
  3.4 Performance of auxiliary equipment
  3.5 Combustion
  3.6 Aptitude with gases other than the reference gas
  3.7 Efficiency
  3.8 Prolonged performance test
  3.9 Time for temperature rise
4 Test methods
  4.0 General
  4.1 Soundness
  4.2 Obtaining the nominal rate
  4.3 Performance safety
  4.4 Performance of auxiliary equipment
  4.5 Combustion
  4.6 Aptitude with gases other than the reference gas
  4.7 Efficiency
  4.8 Prolonged performance test
  4.9 Time for temperature rise
  4.10 Test reports and technical schedules to be supplied
       to the test laboratory
  4.11 Designation
5 Marking
  5.1 Data plate
  5.2 Quality seal
  5.3 Instructions
6 National options
  6.1 Commercial categories in various countries and
       equivalence between the different categories
  6.2 Gases used and supply pressures
  6.3 Gas inlet connections in various countries
  6.4 Water inlet connections in various countries
  6.5 Nominal useful outputs
  6.6 Gas taps
  6.7 Flame failure devices
Annex 1 Test apparatus for type C[1] appliances

Specifies the main constructional and performance characteristics of gas burning appliances for the instantaneous production of hot water for domestic use.