As far as I am aware you do not need anything to look at the parish records, GRO index, census returns etc which are located in the local studies room. However, if you want to view original documents in the archives room, then yes you need a card. In the archives room you fill in a docket with the relevant reference info (found in indexes) and then hand that in at the desk together with your card. Your card will be returned to you when you return the documents. Perhaps also worth noting is that I have never viewed any documents in the archive room that can be photocopied so be aware and take a really good camera if you want a hard copy of an original.
