CCN1 (or a suitable changeover) is required for any operative wishing to work on domestic gas installations and appliances. In addition, the operative must also hold the relevant appliance element relating to the work they wish to undertake.


Course content:

The course covers the following units, plus a group of optional units:

  • Gas safety legislation and standards
  • Gas emergency actions and procedures
    Products and characteristics of combustion (inc. combustion performance analysis)
  • Ventilation
  • Installation of pipework and fittings
  • Tightness testing and purging
  • Checking and/or setting meter regulators
  • Unsafe situations, emergency notices and warning labels
  • Operation and positioning of emergency isolation controls and valves
  • Checking and setting appliance burner pressures and gas rates
  • Operation and checking of appliance gas safety devices and controls
  • Chimney Standards
  • Chimney inspection and testing
  • Installation of open, balanced and fan assisted chimneys
  • Re-establish existing gas supply and relight appliances
  • Inspect, test, commission and maintain gas appliances (Re-assessment only)


Entry Requirements:

For the initial CCN1 assessment candidates must meet the entry requirements as laid out in guidance note 8 for category 1, 2, and 3 entrants (see ACS scheme rules). For re-assessment candidates must have held the element previously – if this has expired within 12 months of the assessment date the initial assessment must be undertaken.

The CCN1 core domestic gas safety certificate has an equivalence to a level 3 QCT qualification in the gas utilisation sector (which is also aligned to ACS) and satisfies the same gas safety criteria leading to a certificate of competence recognized by the Gas Safe Register.


Method of assessment:

Assessment is carried out using a variety of assessment methods including multiple choice, short written response and scenario questions and observed practical assessment.



City & Guilds CCN1


Duration of course

Up to 12 months


Attendance Options


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