The revised RCD guidance in 531.3.3 is precise. The appropriate Type of RCD must be selected, based on the characteristics of the residual current and the equipment that is likely to be connected to the RCD protected circuit".

What I would say is look at the article as a whole, as it makes it quite clear that 531.3.3 refers to 4 Types of RCD, and the points to consider when selecting RCDs for circuits containing various items of equipment. It also makes the point about consulting the manufacturer of the equipment for advice.

Type F RCD Risks:

The term general purpose relating to Type AC devices should not be taken out of context i.e. it is the most basic RCD, suitable for detecting a simple full sine wave residual current at 50Hz. I believe the article makes it clear that the their are 4 Types of RCD that may need to be considered - Quote from the article - The older RCD does seem to be affected by spikes, so likely a SPD would stop it, but a consumer unit is a type tested distribution unit, and to retain the type testing only items recommended by the manufacturer can be used, even if they seem to fit. This handy RC Unit (residual current unit) has been designed for installing on to any standard 1P or 1P+N Eaton MCB with a 10kA, 15kA & 6kA rating to create an RCBO. The MR30 RC POD unit is ideal for standard applications with a 230-240 VAC voltage rating and 30 mA breaking capacity and is field fitable. Fully compliant with Standard 61009, this capable MR30 POD is utilised in numerous industrial and commercial applications due to its versatility and ease of assembly.

In your own words - It is not appropriate electrotechnical language, its generic and anyone following that as a lead will not carry out an appropriate assessment. Type AC RCDs are in clause 531.3.3 of BS7671 2018, because they are still in EN 60364-5-53 2015. The UK have just adopted this line from the EN standard. UK electricians can still make informed technical decisions. This is explained in Chapter 12, 13 and Chapter 30. The Electrician is responsible, not the Technical committee, to make the decision on which device is appropriate for the installation. The revised RCD guidance in 531.3.3 is precise. The appropriate Type of RCD must be selected, based on the characteristics of the residual current and the equipment that is likely to be connected to the RCD protected circuit. and the RCD should be selected based on the characteristics of the connected loads. If you’re not sure about quantities, sizes or have any other questions about your electrical wholesale products, our Electrical2Go sales team will be more than happy to help. Give them a call now on 01424 220384. KEY FEATURES

Type F RCD application example:

Memera 2000AD – These have a narrow terminal and only fit boards specifically marked Memera 2000AD. They won't fit in older boards. So - please help me - have I lost touch with the right places to buy RCDs in the UK? Where can one get a fairly broad selection of different types (A, B) at reasonable price? Why do I find almost entirely AC? The primary principle of an RCD is to protect the persons using the installation, if manufactures are going to be allowed to make equipment that is going to end up in peoples homes then British Standards must make it compulsory for manufactures to state in bold writing how that equipment will affect an installation where RCD's are present, it's already common practice for many manufactures to state what the maximum protective device is to be used with their equipment, so make it their responsibility.