For decades, the issue of hydrogen quality specification has been a source of complexity and confusion in particular for end users, especially because of the jargon spoken by different providers and clients in varied and diverse areas of application. Virtually every requirement was established within the customer–supplier relationship.

The rise of new hydrogen technologies, the emergence of new devices like fuel cells and the spread of knowledge, together with the growing need for uniformity has pushed the specialists to solve this problem. As a result, standardization seems to be the key to accomplish with quality goals at the lowest cost possible. This article discusses the traditional concepts used in the past, the current situation, the standards used today and future developments in hydrogen quality requirements to simplify and facilitate the use and the applications of hydrogen and blends with a careful respect for the quality of the product and safety.