prSSH EN 17921:2025

Natural gas fuelling stations - LNG unloading connector

Scope

This document specifies a harmonized unloading connector for LNG road tanker at LNG fuelling stations. This document is also applicable to LNG RID applications. While LNG is also transported by rail, European regulations are organized through the International Carriage of Dangerous Goods by Rail (RID). The same configuration as defined by this document, can be utilized. This document includes requirements for (at least):
- functional description of the LNG unloading receptacle and LNG unloading nozzle;
- technical layout description of the LNG unloading receptacle.
The technical layout description of the LNG unloading nozzle is not part of this document.
The basic functional requirement of the LNG unloading connector are as follows:
- to prevent leakage of methane during operation and in particular during disconnecting;
- easy handling, no spillage and purging with nitrogen during disconnecting.
The loading connector between the LNG road tanker and the LNG terminal is not covered by this document.
See Figure 1.

Related directives

Directives related to this standards.