There are two standards, ISO 8041:2017 and ISO 5349:2001 Parts 1 & 2
ISO 8041 covers the instrument specification, so things like frequency response, weighting filters, detector linearity, measurement parameters etc.
The SV103 meets the standard.
ISO 5349 is a procedural standard, which tells you what you need (i.e. an instrument which meets ISO 8041), what to measure (e.g. AEQ, triaxial orientation of the hand, etc) and how to do the measurement (practical considerations, what to report, etc).
The SV103A meets both parts of the standard.
The most common misinterpretation of ISO 5349 is that I have heard people saying you cannot use hand-held accelerometers for the measurement. It does not say this in the standard. It discusses both tool-mounted and hand mounted, and in fact, with many tools (e.g. sanders, polishers, planers etc) it is not possible to use a tool-mounted accelerometer.