The Gas Distribution (GD) register was originally held by the Construction Industry Training Board (CITB). It was transferred to the Gas & Water Industry National Training Organisation (GWINTO) ownership in 2000, as part of the establishment of a National Training Organisation for the gas industry.

GD cards were issued following a designated period of off job training and on job experience. The GD scheme predated the introduction of vocational, competence based, qualifications and was therefore never assessed against a performance standard. It was however, the primary method used to train people working on the gas network for many years. It is no longer available as a route to qualification in the industry, having been completely superseded by evidence based qualifications (S/ NVQs) at all levels. The GD cards showed categories ranging from GD1 to GD5 representing the categories of work that the person had been trained on.

Since the demise of the GD training scheme in 2003, all new entrants have been registered using the current Gas Network Operations (GNO) qualification at the appropriate level.

Expiry

The final GD cards expired on 31 August 2008.

Anyone working on the gas network is now expected to have completed a competence based qualification and be registered under Network Construction Operations (Gas) (NCO(G))