Firstly the term 'access' is approached in different ways by different bodies within the uK. The Museum and galleries section of DCMS places its efforts in funding free entry to national museums:

Access is the keystone of the Government's policy on the arts. With funding from the Department for Culture, Media and Sport, the national museums and galleries in England which it supports now offer free entry to their permanent collections to all visitors. [source]

Where as the Museums & Galleries Disability Association is concerned with promoting access for all:

The Museums & Galleries Disability Association (MAGDA) is a not-for-profit organisation promoting the rights of people with a disability to enjoy museums, galleries and heritage sites. It encourages these organisations to achieve access for all, facilitates collaboration between them and those working to improve disabled access and advocates good practice in access for all disabled people. [source]

John Williams, in a disabled access and interactive exhibits meeting with the British Interactive Group points out the terms 'access' and 'disabled' are not interchangeable:

John Williams, the Designer Manager at the Manchester Science Museum, opened the proceedings and during his introduction, challenged the meeting by suggesting that in a debate about "access" the term disabled should be dropped. Museums should in fact be striving to include all groups. He was pleased that in their Museum's corporate plan the term "disabled" will not be found, yet equality of access is still central to their mission. [source]