More than 120 pages of proposed rules, released by the government Thursday, regulate the future of space tourism, touching on everything from passenger medical standards to preflight training.

Before taking a trip that literally is out of this world, companies would be required to inform the "space flight participant" - known in more earthly settings as a passenger - of the risks. Passengers also would be required to provide written consent before boarding a vehicle for takeoff.

Legislation signed a year ago by President Bush and designed to help the space industry flourish at the outset without too much government interference requires the Federal Aviation Administration to conduct a "phased approach" to regulating commercial human space flights.

The first set of regulations, proposed Thursday - dealing with crew qualifications and training and informed consent for passengers - are expected to go into effect next June. Some other safety-related rules cannot by law be issued for eight years unless specific design features or operating practices are brought into question as a result of an incident causing serious injuries or a fatality.

"This means that the FAA has to wait for harm to occur or almost occur before it can impose restrictions, even against foreseeable harm," the proposal says. "Instead, Congress requires that space flight participants be informed of the risks."

Physical exams for passengers are recommended, but will not be required, "unless a clear public safety need is identified," the FAA says in the proposed regulations.

Passengers also would have to be trained on how to respond during emergencies, including the loss of cabin pressure, fire and smoke, as well as how to get out of the vehicle safely.

Pilots, meanwhile, must have an FAA pilot certificate and be able to show that they know how to operate the vehicle. Student or sport pilot licenses would not qualify.

Each crew member must have a medical certificate issued within a year of the flight, and their physical and mental state must "be sufficient to perform safety-related roles," the rules say.

The FAA also would require each crew member to be trained to ensure that the vehicle will not harm the public, such as if it had to be abandoned during a flight emergency.

The legislation that Bush signed tasked the FAA with coming up with rules to regulate the commercial space flight industry, which has been slowly getting off the ground.

Laws governing private sector space endeavors, such as satellite launches, have existed for some time. But there previously has been no legal jurisdiction for regulating commercial human spaceflight.

In 2001, California businessman Dennis Tito became the world's first space tourist when he rode a Russian Soyuz capsule to the international space station. Mark Shuttleworth, a South African Internet magnate, followed a year later on a similar trip, also paying $20 million for the ride.

Last year, in a feat considered a breakthrough for the future of private spaceflight, Burt Rutan won the $10 million Ansari X Prize by rocketing his SpaceShipOne to the edge of space twice in five days.

Two months ago, Greg Olsen, who made millions at a Princeton, N.J., technology company, became the world's third paying space tourist, also on a jaunt to the international space station.

The 123-page proposal was published in the Federal Register, the government's daily publication of rules and regulations, and will be subject to public comment for 60 days, through Feb. 27.

Final regulations are expected by June 23.