Is each Web page defined by a document type?
For each Web page, is the source code valid according to the specified document type (except in particular cases)?
On each Web page, is the default human language identifiable?
For each Web page with a default human language, is the language code appropriate?
Does each Web page have a page title?
For each Web page with a page title, is this title relevant?
On each Web page, is each change in the human language identified via the source code (except in particular cases)?
On each Web page, is each change in human language relevant?
On each Web page, tags must not be used only for layout. Has this rule been followed?
On each Web page, are changes in reading direction identified?