scope:

This Reference Standard addresses the issues arising from the proposal to use Hydrogen as a gas in domestic and smaller commercial properties to evaluate its potential use as a replacement fuel.

Hydrogen as referred to in this document, is as per the specification set out in Appendix 4, and therefore does not cover blends of Hydrogen and NG.

This reference standard covers Hydrogen installations in domestic and small commercial premises downstream of the supplier's emergency control valve (ECV) and:

• supplier's meter installation is considered in terms of location, ventilation and general meter installation materials and components but excludes the design and construction of the meter itself

• maximum operating pressure (MOP) of the installation pipework is not exceeding 25 mbar

• supply pressure is assumed to have a MOP of 75 mbar.

Standards development in the first instance is to consider domestic and smaller commercial gas infrastructure and will exclude the following:

• dual fuel engines

• gas turbines

• any standards related to upstream of the suppliers ECV

• educational establishments

• processes and industrial plant

• multi-occupancy buildings

• large commercial buildings that are considered to have non-domestic appliances

• energy centres and plant rooms with cascade boiler systems

• garages and body shops facilities

• caravan parks and boats, yachts and other vessels

• bottled gas supplies

• gas fire pits, lamps and vehicles

• commercial catering.

Italicised text is informative and does not represent formal requirements.

Appendices are informative and do not represent formal requirements unless specifically referenced in the main sections via the prescriptive terms "should", "shall".