To join Napit you need to have had an apprentiship or equivelent training,17th edition and 2391
I believe the 17th and 2391 requirements can be set aside and required within 12 months if someone doesn't already have them
So in your case the training seems ok
The 2391 is ok
That leaves just the 17th edition,which they will probably wave for 12 months in your case
That is the personal requirements,you then have to comply with the other requirements
You must have acess to calibrated test gear Earth loop tester.insulation/continuity and RCd or one of the modern all in one pieces of crap that everybody seems to have nowadays,also an approved voltage tester
You will be given an assessment where you will be expected to demonstrate that you are competent using these instruments
You say that somebody else was doing the testing in your last job,I assume that you are competent testing because you will have to demonstrate testing to the assessor
There are other things that will be asked for,but these will be mostly beurocratic nonesense requirements that the government made them include
You will be able to carry out PIRs with Napit,but you must be in possession of public indemnity insurance before they will let you use their paperwork for that
It is a good organisation for self employed electricians,far superior for the one man bands than the NIC
If however you require registration for generating work,then the NIC are far better known amongst suppliers of work such as councils.insurance companies/letting agents,if that is the case,the NIC would be better dor you
The ECA/elecsa scheme is also very popular and the reqirements are similar excepting the 2391
The NIC have the lowest entry requirements though and seperate assessments are required for PIRs
Looking at each schemes website is the best way to compare and chose
Finally the one requirement that they all insist on,is the cheque for your entry
Word has it that in the end the only real interest any of them have is the accumalation of funds