Under the BSI model, any organization, association or group who wish to document standardized best practice on a specific subject can commission a PAS, subject to the BSI acceptance process.
A British Standard and a PAS must reach full consensus between all stakeholders on technical content.
The timescale for the development of a PAS can be shorter, typically around 8 months, and is why it is sometimes referred to as a 'fast-track standard'.
It is also written in accordance with BS drafting rules, which means that the content must be technically robust and cannot be technically constrained (i.e. it cannot include patented or proprietary methods or products).
However, not all PAS documents are structured as specifications and the term is now sufficiently well established not to require any further amplification."