Airlines are not obliged under the regulation to make available the rules and regulations as set out. However, many airlines do lay out their policies on carrying medical oxygen on their websites.
The rules themselves are widely available. EU regulation 1107/2006 is published on the EU Commission website. Its obligations are explained in the Department for Transport code of practice, “Access to Air Travel for Disabled Persons and Persons with Reduced Mobility”. The Department for Transport and the Equality and Human Rights Commission have also published a step by step guide called "Your rights to fly—what you need to know":
http://www.equalityhumanrights.com/your-rights/rights-in-different-settings/air-travel/your-rights-to-fly-step-by-step-guide/
http://www.dft.gov.uk/transportforyou/access/aviation shipping/yourrightstofly
Free copies of these documents are available from the Department and the Equality and Human Rights Commission website. Copies have also been placed in the Libraries of both Houses of Parliament.
Airlines based in countries outside the EU are governed by the laws of the state in which they are registered. Passengers needing assistance once they reach the UK should notify the airport where they will arrive 48 hours in advance of their requirements, either through their airline or travel agent. Passengers should always check before they buy a ticket whether the air carrier they choose to fly on offers them the service they want.