Certified Copies - who can certify?

My question is about certified copies of documents.

I am granting 4 new leases of terms greater than 7 years and these will be registered using form AP1. I have drafted the leases myself and am dealing with all aspects of the matter, including helping the tenants with the application for registration. Neither I nor the tenants are employing a solicitor or conveyancer. 

The Practice Guides state that only certified copy documents should be submitted (with a few exceptions, none of which apply) and that these will be destroyed after registration.

Can either I (as the landlord) or the Tenants certify the documents as being true copies of the originals?

Also, how do I deal with evidence of identity without using a solicitor or conveyancer?

Thanks.

My principal query still stands but I now know the answer to the question in my last paragraph.

Kenward - the person submitting the application can certify the documents as copies 
See PG 67 re identity verification guidance - Practice guide 67: evidence of identity - GOV.UK