This is the card specifications for the ECS card, this tells you the qualifications required or each card, the information for this is available on the
ECS website.
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The 2400 is an entirely different qualification and whilst it may help with assessing the design of an installation it is not directed to periodic inspections like the 2395.
Being able to do periodic inspections is not dependent on an examination but on experience and understanding, the qualifications will help with this but it is not a requirement (except for some employers), though it may help demonstrate competence.