These documents should not be used as an excuse for not generate contained through (X) HTML + CSS. In general must not be abused for PDF documents to provide information, by using them Only in certain situations, such as brochures, legal documents or documents to the extensive nature, it is useful to provide a downloadable version and printable.
To generate PDF documents accessible it is imperative that the official managed through a word processor (office word, free office, etc.) easily accessible. To generate these documents accessible you can follow the indications given in the following guides.