Hydrogen and Fuel Cell Safety

You are here:Archives > March 2010 > Int'l WG Meets in Paris

International Working Group on Hydrogen Refuelling Stations Meets in Paris
Karen Hall, National Hydrogen Association

On February 24-25, ISO/TC 197 Working Group (WG) 11 met in Paris to address the Compilation of Comments from circulation of the Committee Draft. The meeting also provided an opportunity to update the WG in progress from the two active Task Groups:

Task Group 1 on separation distances
Task Group 2 on dispensing

Highlights of Discussion and Issues
At the 2009 Plenary meeting, ISO/TC 197 changed the scope of ISO 20100 as follows:

This international standard specifies the design, operation and maintenance characteristics of standalone outdoor public and non-public, and indoor warehouse fuelling stations that dispense gaseous hydrogen used as fuel onboard land vehicles of all types.

Residential and home applications to fuel land vehicles are excluded from this technical specification.

The fuelling station may comprise, as applicable, the following as shown in Figure 1:

Delivery of hydrogen by pipeline, trucked in gaseous and/or liquid hydrogen;

On-site hydrogen generators using water electrolysis process or hydrogen generators using fuel processing technologies;

Liquid hydrogen storage, pumps and vaporizer;

Gaseous hydrogen compression and purification systems;
NOTE When the fuelling station comprises an on-site hydrogen generator, a compressor/purifier system is commonly integrated into it.

Gaseous hydrogen buffer storage;

Pre-cooling device;

Gaseous hydrogen dispensers.

The addition of "standalone" in the scope creates an issue because the aim is to integrate hydrogen with other fuels. This was added because of ISO timetable and plans to include integration issues. It was noted during the WG 11 meeting that energy companies have no use for a document for standalone hydrogen stations. As the hydrogen processing equipment is standalone, the WG need only address integrating the dispensers – deal with safety distances and hazard zones. Task Group (TG) 2 could look at this work, since it is about dispensers.

The WG discussed the opportunity to apply the SD table (Standard safety distances for passive gaseous hydrogen systems – NEW) to integrated hydrogen refuelling stations – TG 2 took this action item and agreed to work with TG 1 on layouts.

The table created by TG 2 will be retained as an Annex. TG 2 is to complete detailed review to ensure all elements of the table are reflected in the text of Chapter 7 and Chapter 11.

The addition of indoor refuelling is to be addressed by TG 1 prior to circulation of the Draft International Standard.

Since operations and maintenance was added to the scope of the document, an issue was raised of the need to avoid replacing hoses with hoses not fit for hydrogen use, or maintenance personnel accidentally replacing a 350 bar hose and nozzle assembly onto a 700 bar dispenser. If this were to occur, a 350 bar car would be able to connect and overpressure could occur. The question was raised: Do we need unique standardized fittings for all connection points?

An additional call for experts is needed to address the change in scope. Participating countries are asked to seek representation with operation and maintenance expertise, and report back to the convener.

Next Meeting
The WG is looking for an opportunity to meet in September in Japan. The Japanese experts are to consult with their national committee and propose a date and location.